PREDICT 2 Study Experience: Set-up Day + The Study Pack

This post is the second of a series on my participation in the PREDICT 2 study. Click here to read the first post of the series.

Today was set-up day. I started off with a coworker (and friend, @Meghan) helping me install the glucose monitor on my left (non-dominant) arm. It takes 16 hours or so to calibrate, and I’ll keep it on for the duration of the study. Later I also “activated” my activity tracker (“activate” being I took it out of the package and put it on my left wrist like a watch).

Later in the morning I did potentially the strangest thing I’ll ever do at work. I’ll spare you the details; I’ll just say that the stool sample had to be collected during the set-up day so I did what had to be done. 

Before lunch I gave my saliva sample, which was quite literally spitting into a tube. I carried all of my samples home, and I’ll mail them back later this week. I had a call with a nutritionist from the study on my way home from work, and she confirmed that I had done all of my to-do items for the day. She talked me through the first couple of days of the study, asked if I had any questions, and let me know that if I ever needed anything, someone from the study would be able to chat with me through the app. That’s definitely a benefit to having collaborators from both the U.S. and the U.K. – different time zones so someone is always available for the study participants.

For tomorrow, “day 1,” I’ve got my standardized breakfast defrosting in the refrigerator and my standardized lunch ready to go. It looks like it’s muffins and chocolate shakes for me tomorrow! Of course, I can eat whatever I want for dinner, and I’ll just need to do some careful logging of the ingredients and serving sizes so the study team knows what nutrients I’m consuming. 

Standardized meals for day 1 of the study. I’ll scan the barcodes with the app to log each meal.

The study pack

I received my study pack in the mail on the Friday afternoon before I would begin the set-up day on a Monday. The box had several smaller boxes inside with labels and storage instructions. There was a long, thin box labeled “muffins” that I stored in the freezer, and I put a smaller box of other shelf-stable food items in the refrigerator. Non-food items included:

  • Food scale for weighing food ingredients for my meals that are not standardized by the study team
  • Cup and shaker for preparing shakes
  • Photo card for taking pictures of all the non-standardized meals that I eat
  • Study guide with information about the study
  • Tape measure for doing body measurements
  • Wearable activity tracker
  • Glucose monitor, reader, and adhesive patches
  • Return boxes for samples and devices
  • Sample collection kits for at-home collection and in-lab collection

My experience so far has been that the study team is extremely organized and prepared. In a white paper prepared by the ZOE team (“Overview of The ZOE Scientific Project for Researchers & Clinicians”) in June 2019, the authors mentioned that the PREDICT 2 study includes upgrades from PREDICT 1 that “improve data collection” and “reduce participant burden.” I’m pondering if those upgrades include the study pack experience because everything is extremely organized, and I can see how an unorganized box would be particularly disconcerting for the study participant, especially at the beginning of the study. 

That’s all I have for today, the set-up day. Tomorrow I’ll be posting a day 1 reflection as well as discussing the study that started it all: PREDICT 1.

Forging the Future of Personalized Nutrition: My Experience, My Contribution

Introducing the PREDICT 2 Study

I am less than 48 hours away. 48 hours away from beginning my participation in a study that will potentially provide insight into how my body metabolizes food. Not how people my age/gender/race tend to metabolize food, but how my body uniquely metabolizes food.

This study is riding the wave of personalized nutrition that’s been surging through the scientific community for the last decade. Because as scientists learn more and more about nutrition and the digestive system, the clearer it becomes that metabolism is a deeply personal experience.

Imagine this. Instead of following the latest popular diet (i.e. gluten-free, paleo, keto, intermittent fasting), people have the opportunity to take a test to identify their unique responses to different foods. For example, a gluten-free diet may work for some (Celiac disease, gluten intolerance), while for others there might be something else in wheat products that’s causing them discomfort. In theory, this test could identify what “something else” is. 

PREDICT 2

The study is called PREDICT 2, and it involves following a schedule of eating pre-prepared meals and providing blood, saliva, and stool samples for analysis. “PREDICT” stands for “Personalized Responses to Dietary Composition Trial,” and I’ll talk more about the study, its sponsor (a commercial company, Zoe Global Limited), and the collaborators involved (Stanford University, Massachusetts General Hospital, King’s College London, and Tufts University) in more detail later this week. I’ll also be blogging about PREDICT 1, a two-week study that measured physiological responses to specific foods. Researchers showcased preliminary results from PREDICT 1 at the American Society of Nutrition conference early in summer 2019.

12 Days

The study will take place over 12 days: one set-up day, 10 study days, and one follow-up visit to a clinic where I’ll have blood samples taken. I received my study pack in the mail two days ago, and it contained all of the items I’ll need throughout the study, including the standardized meals. 

On some days, I’ll have standardized breakfast and lunch meals that I’ll eat. Depending on the day and the samples I need to provide, I’ll need to wait 2-4 hours after each standardized meal before eating again. I can drink water, coffee, and tea during these times, but they recommend that I drink about the same amount of caffeine that I normally do every day.

I’ll log all of my non-standardized eating and drinking activity in a mobile app I downloaded on my phone. If you’ve ever used My Fitness Pal to track calories and nutrients you’ve consumed through food, the app as very similar to that.

Samples

On the set-up day, I’ll use materials I received in the study pack to collect a stool sample. This sample allows scientists to analyze the diversity of my microbiome, which is key to understanding my body’s unique response to certain nutrients in food. I’ll also collect a saliva sample on the set-up day, which provides the study team with samples of my DNA. The study team describes that DNA samples enable them to “identify certain genetic characteristics that have been previously associated with [my] responses to foods that [they] will measure during the study.” 

On some days, I’ll provide blood samples at specific times before and after meals. From these samples, study scientists can learn about how my blood fat levels change throughout the day and before and after specific meals. The study team describes blood fat levels as a “key metabolic indicator and one of the two main sources of energy in your body,” with blood sugar, or blood glucose, being the other main source of energy.

To measure blood glucose, I’ll be wearing a blood glucose monitor* throughout the study. I activate the monitor myself on the set-up day, about 16 hours before the first study day. The monitor takes this time to calibrate.

*This glucose monitor is FDA-approved for use in the management of diabetes but not for evaluating blood sugar levels in non-diabetic contexts, including this study

In addition to the glucose monitor, I will also be wearing an activity tracker on my nondominant wrist throughout the study to measure my physical activity and sleep levels. This tracker is very similar to FitBit technology.

After the 10 study days, I will visit a Quest Diagnostics Patient Service Center to provide a blood sample. The study team requires that I do this within one week of the tenth study day and before 11:00am so the samples can be shipped and processed at a central lab the following day. 

All of the sample analysis relies on knowing exactly what I consumed to elicit certain physiological responses. Thus, it’s crucial that I follow the food and drink schedule as closely as possible, eating and drinking standardized meals and drinks when scheduled and carefully recording my food and drink consumption at all other times.

Logistics

I am not getting paid to do this study, but I am pretty pumped about getting my results back. The study team is hoping for 1,000 participants, so potentially you could be involved too! A few months after the study, I will be contacted by the study team to discuss my results. If I want them to, they can also share the results with my primary care physician. Essentially, I’m hoping for information on my personal physiological response to components of different foods and how those responses compare to common responses to food. 

While the insights gleaned from this study will likely help build an algorithm for predicting individual responses to food, the informed consent form states: “the predictive value of this research is not yet proven and it is unknown whether you will benefit from the information”

Over the next couple of days, I’ll be posting regular updates about the study as well as providing background information about the people and science involved. I’m really excited (as nerdy as it sounds) to participate in a study that’s doing awesome things for science by learning how different people respond to different foods and what factors account for those differences. I hope people will ask questions about my experiences and be inspired to participate in meaningful studies like this in the future!

Note: While the PREDICT 2 study team encourages participants to share information about the study, the statements made in this blog post and future blog posts are based on my own research and sets of opinions. 

This blog post is the first in a series on my participation in the PREDICT 2 study. Click the links below to read earlier parts of the series:

Consider Giving Rye a Try

What is rye?

Rye is that bread that’s offered as a choice for your sandwich that you don’t choose because you don’t quite know what it is, although the term “rye” isn’t exactly foreign to you. Rye bread comes from rye flour, which comes from rye grain, and it often has more fiber than white bread does. Rye bread is usually darker and has a stronger flavor. But these superficial differences are only the beginning of the story.

More or less born in what is now present-day eastern Turkey, rye is rich with lactic acid bacteria, which serve a dual purpose: ferment the dough + make changes to the bioactive compounds unique to rye. Rye bread is known for its surprisingly beneficial impact on insulin metabolism; the academic jury is still out as far as to why, but a prime suspect remains: rye’s production of branched-chain amino acids and amino acid-containing small peptides.

Bread often gets a bad rep for instigating a high glycemic response (increased levels of glucose entering the gut following a high-glycemic meal triggers increased production of insulin). Interestingly, rye bread triggers a relatively low glycemic response and actually improves blood glucose (blood “sugar”) levels, occasionally called the “Rye Factor” (don’t read this the wrong way. Rye bread is still mostly carbohydrates). 

Rye is also associated with a reduced risk of heart disease. No surprise here; anything that helps regulate blood glucose levels is likely to positively influence the heart and reduce the risk of disease. 

A key part of the unique rye narrative is the bioactive (read: biologically active = bioactive), or bioavailable, compounds (I also talk about bioactivity in my recent article about naturally occurring iron levels [check it out]). When compounds are more bioactive or bioavailable, it means they exist in a form that can be readily absorbed and utilized by the body. 

Picture this. You’re eating a sandwich on rye. Bioactive compounds from rye enter the gut (more scientifically, the gastrointestinal tract or “GI” tract) and bacteria living in the gut (good guys) process these compounds into a form that the body absorbs and uses. Without the right factors present to make these compounds usable by the body, they’d be nearly useless.

Rye is one of many plants that contain unique bioactive compounds, often called phytoactive compounds or phytonutrients (phyto = plant). Phytonutrients are beneficial to the human body in a different way that macronutrients (fat, carbohydrates, protein) and micronutrients (vitamins and minerals) are. Lots of studies from a continuously growing body of research associate phytonutrients and plant-based eating with reduced risk of disease, from heart disease to cancer. Interestingly, research also shows that gut bacteria regularly transform phytonutrients into more bioactive forms.

The research

My background discussion on rye got a bit out of hand (that tends to happen when you get me talking about phytonutrients and bioavailability), but let’s not forget the recent research study that prompted this post. From the University of Eastern Finland, published in the journal Microbiome, researchers investigated the contributions of lactic acid bacteria from rye and gut bacteria native to the human body. They found that the two populations of microbes produce similar compounds that contribute to health benefits associated with rye; innate human gut bacteria produce derivatives of betaine, which is also found in rye.

Betaine is associated with a reduced need for oxygen in heart muscle cells, a decreased risk of dangerous reduced blood flow, and potentially increased heart muscle performance.

The study used a) metabolomics to compare the metabolites found in rye versus naturally in the human body and b) mice and human gut models to determine the impact of gut bacteria versus lactic acid bacteria from rye. These two approaches enabled the researchers to confirm that the unique metabolites identified indeed originated from rye, as opposed to somewhere else in the human gut.

Make the rye-t choice

While I don’t intend to endorse rye as the bread of choice, I do think this discussion of rye, lactic acid bacteria, and phytonutrients is intriguing. Rye truly arrives at the party prepared to provide both the healthy compounds and the tools needed to unpack and serve those compounds for absorption and use in the human gut. I might invite rye to my next sandwich party…

Note

I’m still pondering how I can improve the “prepared party guest” analogy to describe rye and its unique components. Got an idea on how to improve it? Email me at ScienceKara.com.

Fun fact

Rye was recently selected as Finland’s national food.

Press release

Journal article

If this article has you thinking more about whole grains, I wrote an article on this topic when I worked at the North Carolina Research Campus in Kannapolis. Check it out. 

What Your Naturally Occurring Iron Levels Say About You

Iron: too much and you’re at risk for liver disease; too little and you’re anemic. As much as 18% of Americans use a supplement containing iron, but a new study published in both the Journal of the American Heart Association and PLoS Medicine made connections between naturally occurring iron levels and more than 900 health conditions.

With more than half a million individuals’ genetic data making it possible, the study focused only on naturally occurring iron levels (as opposed to iron levels impacted by supplementation). Genetic variation leads to different levels of naturally occurring iron among individuals, just like genetic variation leads to blonde and brunette hair or short and tall people.

Interestingly, naturally higher iron levels were associated with potential benefits and potential risks that seemed, at least in part, contradictory. 

Potential Benefits of More Naturally Occurring Iron

People with genetic variants leading to naturally higher iron levels were also (on average) associated with having a lower risk of high cholesterol levels. Too much cholesterol and it’ll build up in the arteries and increase the risk of blocking blood flow. More here

Additionally, naturally higher iron levels were associated with a reduced risk of clogged arteries, like what can happen with excessive cholesterol levels in the blood, which can lead to health conditions like stroke, deep vein thrombosis, and atherosclerosis. 

Potential Health Risks Associated with More Naturally Occurring Iron

The study also found that higher naturally occurring iron levels were linked to higher risk of blood clots as a result of slow blood flow. More on poor circulation here

Higher naturally occurring iron levels was also found to be associated with higher risk of bacterial skin infection.

Making Sense of the Results

In a very unsatisfying conclusion, lead study author Dr. Dipender Gill essentially said that there is still a lot scientists don’t understand about how iron levels influence the relationship between cholesterol levels, circulation, and blood flow-related health conditions like stroke, deep vein thrombosis, and atherosclerosis. 

It’s likely that the same genetic variation responsible for different levels of naturally occurring iron influences individual risk for conditions like high cholesterol, poor circulation, or stroke. Perhaps in future studies, Gill and the research team will control for different factors (age, sex, BMI, etc) to see what health differences make higher naturally occurring levels of iron beneficial versus potentially harmful.

Iron Basics*

As a component of hemoglobin, iron helps carry oxygen around to the body’s tissues like the wheels of a taxi carrying humans from point A to point B. In addition to being oxygen’s preferred form of transportation, iron provides support for:

  • Metabolism
  • Growth and development
  • Normal cellular functioning
  • Hormone production
  • Connective tissue production

So yeah, iron is pretty important. But the name of the game when it comes to iron intake is balance. Too much? Liver damage. Too little? Anemia.

Recommended Dietary Allowances (RDAs) for iron intake vary based on age and, for women, pregnancy status (PSA: these recommendations were developed by the Food and Nutrition Board (FNB) at the Institute of Medicine (IOM) of the National Academies (formerly National Academy of Sciences)).

Image credit: National Institutes of Health Office of Dietary Supplements

You can get iron from all sorts of dietary sources. Plants like nuts, beans, and vegetables along with iron-fortified foods contain nonheme iron, while meat, seafood, and poultry contain both nonheme and heme iron, which is more biologically available, or bioavailable, for absorption during digestion. Think of it like this: an amount of iron in a piece of steak is more “valuable” to you than the same amount of iron in your spinach salad. Heme iron gives you more bang for your buck. That being said, vegetarians and vegans need to eat a lot more to get enough iron for good health.

Iron Supplements: Synthetic and Whole Food

The average iron supplement provides 18 mg of iron. However, multivitamins for women most always contain iron while multivitamins intended for men and for seniors often do not. Iron-only synthetic supplements typically deliver more than the RDA, as much as 360% (65 mg). 

Whole food iron supplements usually contain a percentage of iron that’s closer to the RDA, closer to 10%. Ingredients in natural supplements based on whole foods are arguably more bioavailable than synthetic supplements because they imitate how those ingredients are found in nature. So the 10% of iron in a whole food supplement will be absorbed in the body at a higher rate than the 360% in the synthetic supplement. Natural supplements that deliver a nutrient in its “natural habitat” – a whole food matrix. This delivery method is more aligned with what the body needs. Although, ultimately a whole food source of iron is the superior choice to any sort of supplementation.

What other questions do you have about iron? Let me know at ScienceKara@gmail.com

*Courtesy of the National Institutes of Health Office of Dietary Supplements

Tart Cherries & Metabolic Syndrome

A recent study found that a specific type of tart cherries can improve health conditions for adults with metabolic syndrome, which I blogged about not too long ago. For this blog post, we’re traveling to an area of France just north of Paris…

Montmorency tart cherries look just like the little cherries you’ll find while playing Pac-Man. These cherries are bright red and not sweet – not your normal grocery store cherries. But they’re packed with beneficial compounds unique to plants called phytonutrients. In this case, we’re focusing on a specific type of phytonutrient: anthocyanins.

Know Your Cherries

Cherry Type Taste Color Health Benefits
Rainier Cherry Sweet Yellow No Anthocyanins
Bing Cherry Sweet (slightly more so than Rainier) Dark Red Anthocyanin-rich + anti-inflammatory properties
Montmorency Cherry Sour/tart Bright Red Anthocyanin-rich + cherry type most often studied for potential health benefits

Know Your Anthocyanins

Anthocyanins are in the flavonoid family of polyphenolic phytonutrients. Like all phytonutrients, they are non-nutritive bioactive compounds, non-nutritive meaning they are healthy in a different way than macronutrients (protein, fat, carbohydrate) and micronutrients (vitamins and minerals). Like some other phytonutrients, anthocyanins provide both health benefits and pigmentation (reds, purples, and blues).

About Montmorency Tart Cherries A.K.A. Prunus cerasus

Montmorency tart cherries get their name from the first place that ever cultivated them in the 18th century, a commune in the northern suburbs of Paris, France. Now, Montmorency tart cherries are the most common variety of tart cherries grown in the United States; three-fourths of all Montmorency tart cherries grown in the U.S. are grown in Michigan.. They are available year-round in various forms: dried, frozen, canned, juice, and juice concentrate.

Both the bright-red color and sour-tart taste of these cherries come from their rich supply of polyphenols. In addition to anthocyanins, Montmorency tart cherries also have kaempferol and quercetin (also flavonoids) and chlorogenic acids (a type of phenolic acid and the main polyphenol found in coffee).

Additionally, Montmorency tart cherries are a rich source of melatonin, which is associated with sleep. These tart cherries actually contain six times more melatonin than Balaton tart cherries. Interesting fact – if you’re consuming tart cherries for sleep reasons, you might be better off eating straight cherries instead of juice because melatonin is unstable and may degrade during juice processing.

Montmorency Tart Cherries: A Small Pilot Study

A research group from the University of Hertfordshire (Hatfield, UK) published the results of a small study recently in the Journal of Functional Foods. Why study tart cherries? Lead author Terun Desai attributes the healthy qualities of Montmorency tart cherries to the “synergistic influence of anthocyanins, other polyphenols, and fiber.”

Desai’s small pilot study was the first to study Montmorency tart cherries in the specific context of metabolic syndrome, which affects 35% of U.S. adults.

Researchers conducted a randomized, placebo-controlled crossover trial. The study lasted six weeks with a 14-day washout period and included 11 male and female participants between the ages of 37 and 61. Participants had to meet at least three of these metabolic syndrome criteria defined by the study:

    • Waist circumference >35” (female) or >40” (male)
    • High or borderline high triglyceride levels
    • Low HDL
    • High blood pressure
    • High fasting blood sugar

Note: These five metabolic syndrome parameters are slightly different than the four parameters I list in my blog. I list “dyslipidemia” which includes both low HDL, high LDL, and high triglyceride levels. Additionally, “insulin resistance” goes hand in hand with “high fasting blood sugar.”  This is because when cells are resistant to insulin, glucose levels in the blood increase even when you haven’t had a meal in a while (“fasting”).

Participants consumed each of these three things on three different occasions, each separated by two weeks:

    • Montmorency tart cherry juice
    • Montmorency tart cherry capsules
    • Placebo drink

The cherry juice and cherry capsules contained the same amount of anthocyanins, and they matched about the same number of whole tart cherries. The placebo drink tasted just like the cherry drink, with the study scientists controlling for taste, calorie count, and visual appearance.

Scientists regularly monitored parameters like:

  • Heigh, weight, and waist circumference
  • Arterial stiffness, blood pressure, and heart rate
  • Cardiac output, stroke volume, and mean arterial pressure
  • Total peripheral resistance and resting metabolic rate
  • Glucose and insulin levels, insulin resistance or sensitivity, and blood lipids

Don’t know what all of those words mean? No worries. Basically, all of these measurements were taken because the values are associated with heart and metabolic health. The study scientists wanted to see how each of the three consumable components affected or did not affect these measurements.

Ultimately, their research led to the conclusion that Montmorency tart cherry juice produces a “significant, clinically-relevant” reduction in systolic blood pressure compared to the placebo drink. As a reminder, “systolic” blood pressure refers to the first or top number in a blood pressure reading, i.e. the “120” in “120/80.” This reduction was seen just two hours after consumption. Both the cherry juice (at one hour) and the cherry capsules (at three hours) showed an insulin-lowering effect.

The study scientists acknowledge (rightfully so) that their results are preliminary and more research should be done before making more concrete claims. There were only 11 people in this study, and the more people in the study, the more reliable the results!

Interestingly, the scientists originally thought that the Montmorency tart cherry capsules would produce greater effects on metabolic syndrome parameters than the cherry drink. The logic behind this is that the anthocyanins in the capsules would be more biologically available, but there really wasn’t a huge difference in effect between cherry juice and cherry capsules.

Read the press release

Read the study

Other sources

ChowHound

Journal of Agricultural and Food Chemistry

Something to Say About Soy

Apparently the U.S. Food and Drug Administration (FDA) is planning to remove soy from the “official” list of heart healthy foods, but a group of Canadian scientists have something to say about it.

(Note: I couldn’t find a press release from the FDA announcing the removal of soy from the heart healthy list, but should I find it, I will attach it here.)

I’m working on an article right now about lipoproteins, but here’s a brief description to get us started. High-density lipoprotein (HDL) is usually referred to as “good” cholesterol, and this is because it is associated with clearing cholesterol from the body through the liver and preventing plaque build-up in the arteries (plaque build-up is bad; it leads to heart disease).

Low-density lipoprotein (LDL) on the other hand is the “bad” cholesterol, and it gets its bad rep from its association with coronary artery disease and carrying cholesterol to the arteries. The general goal is to maintain high levels of HDL and low levels of LDL. Stay tuned for more on lipoproteins.

The study was a meta-analysis of 43 existing trials evaluating soy to determine whether removing soy is the right move or not. Meta-analyses take one subject and quantitatively analyze a variety of different studies that all focus on that one subject.

Out of 43 trials, 41 examined soy protein and its effect on LDL. All 43 trials contained data about “total cholesterol.”

For reference, results from a typical blood test you might have at your annual doctor’s appointment will report on:

  • Presence of anemia or infection
  • Kidney and liver function
  • Electrolyte levels
  • Diabetes status
  • Thyroid function
  • Cholesterol levels

Among the cholesterol levels, the lab will report on:

  • Total cholesterol
  • LDL cholesterol
  • HDL cholesterol

In this particular research article, scientists highlighted a soy protein that reduced LDL cholesterol by three to four percent. The lead author of the study says that this number is small but significant and that reducing saturated fat and cholesterol-rich meat consumption in a diet that includes soy protein could be even more beneficial for cholesterol levels.

Researchers from this study only examined research studies that the FDA has referenced in the past, and the lead author (from St. Michael’s Hospital in Toronto) pointed out that soy protein, as a part of a plant-based diet, is “in line with Health Canada’s recently released food guide.”

Read about that food guide here.

St. Michael’s Hospital press release

What is Metabolic Syndrome?

You might have heard the term “metabolic syndrome” and envisioned it as some sort of specific disease, but it’s not quite a “disease” in the typical sense. Metabolic syndrome is better described as a health state in which you are at an increased risk for conditions like diabetes, hypertension, and heart disease.

Metabolic syndrome has been defined in a few different ways. Here are a couple of different explanations:

Depending on how many metabolic risk factors you have, you could be classified as having “metabolic syndrome.” The four health states listed under the NCEP/ATP III definition can be considered as “risk factors” for metabolic syndrome. There are a lot of science-y words in that definition, so let’s break it down.

  • Central obesity: Fat accumulation in the abdominal area, which is particularly associated with obesity and its negative effect on health.
  • Dyslipidemia: Unhealthy levels of lipids (fat) in your body. This could either be too-low levels of “good” HDL cholesterol, too-high levels of “bad” cholesterol “LDL,” or too-high levels of triglycerides (TGs) – a type of fat saved as energy when your body can’t use all of the calories you’ve consumed.
  • Hypertension: It’s basically common knowledge that high blood pressure isn’t a good thing, but why is that again? When you have high blood pressure, it means your heart and arteries are working extra hard to pump blood through the body. Remember, blood carries nutrients and oxygen that all of your cells rely on to survive.
  • Insulin resistance: People develop type 2 diabetes when their cells form a resistance to insulin. Insulin is the hormone that facilitates the use of glucose for energy, so when cells aren’t responding to it, glucose levels in the blood increase. High blood glucose levels cause a myriad of problems, plus it means that your cells aren’t getting the glucose they need.

Mechanisms Behind Metabolic Syndrome

Metabolic changes leading to heart disease, diabetes, and hypertension don’t happen overnight. Lifestyle choices like diet and physical activity levels play a huge role in metabolic syndrome development, but some factors are unavoidable. For example, risk for metabolic syndrome increases with age.

Physiological changes in the body as a result of certain lifestyle choices like poor diet and low exercise levels lead to underlying, systemic inflammation, and oxidative stress. These metabolic changes are what ultimately lead to conditions like heart disease, diabetes, and hypertension.

Prevent or Manage

A healthy diet and active lifestyle can help prevent metabolic syndrome (and a lot of disease, really), but these qualities can also help manage metabolic syndrome if you’ve already started to develop it. Healthy food and physical activity support the liver and help your body better manage glucose.

For example, antioxidants found in micronutrients and phytonutrients like vitamin C, vitamin E, and beta-carotene can address oxidative stress. Antioxidants also promote healthy glucose metabolism and diabetes prevention, and they are associated with reduced risk of heart disease.

Ultimately, the solution here isn’t shocking. Eat healthy food. Be active. Reduce your risk of metabolic syndrome.

(*drops the spinach*)

You, Your Metabolism, and Science: How Research Studies Can Fight the Obesity Epidemic

Note: This is an article I wrote that was originally published on TransformingScience.com.

The one-of-a-kind Human Whole-Room Calorimeter at the UNC Chapel Hill Nutrition Research Institute can be used for a wide variety of research studies. Read on to learn about how this technology works, how experts at the Appalachian State University Human Performance Laboratory are studying metabolism, how these studies are vital for improving human health, and what a typical day as a study participant is like (including getting paid).

ABOUT THE CHAMBER

What they call the Human Whole-Room Calorimeter or Metabolic Chamber is essentially a small room that can calculate how much energy (calories) a person expends (both while resting or moving). This is balanced with the energy taken in through the diet over a 24-hour period. By controlling what you do and what you eat while in the chamber, researchers can accurately measure how much energy it takes to do certain things.

The metabolic chamber at the Nutrition Research Institute (NRI) is equipped with a bed, toilet, and sink. It also has the space to accommodate a treadmill or a stationary bike depending on the requirements of the study being conducted. Research staff can send food and other items through an airlocked compartment, and there are also ports for blood draws if a certain study requires them. There is also a television and – of course – WiFi.

The metabolic chamber is unique; there are only about 26 other similar rooms in the country, and it’s the only one in the Carolinas. This type of technology is essential for researchers who want to study energy balance and fuel use.

The first chamber study was conducted in 2011. The NRI and teamed up with the Appalachian State University (ASU) Human Performance Laboratory, recruiting 10 male participants to test the effect of 45 minutes of vigorous cycling on post-exercise RMR as measured in the metabolic chamber and contrasted with a rest day to determine how much and how long that exercise affected post-exercise energy expenditure. They found that 45 minutes of vigorous exercise resulted in 519 more calories burned compared to the rest day, and post-exercise calorie-burning was significantly elevated for 14 hours, resulting in an additional 190 calories expended, again compared to the rest day.

PARTICIPATING IN A CHAMBER STUDY 

The DEXA

Orientation and baseline testing is the first step of any chamber study. Before your first day in the metabolic chamber, you’ll have a DEXA (Dual-Energy X-ray Absorptiometry) scan done at the NRI as part of your orientation and baseline testing. This machine provides precise measurements of total and regional body composition through high-resolution imaging. However, it is noninvasive and includes very low radiation exposure. Plus, you’ll be able to have a copy of your DEXA results, which include measurements like percent body fat, resting metabolic rate, and bone mineral density.

On your day in the chamber, you’ll arrive at the NRI in the morning between 7:00 and 7:30 to change into (very comfortable) scrubs and take any necessary measurements before entering the chamber around 8:00. Once you’re in the chamber, you can essentially do whatever you want (read, watch TV, use your laptop) as long as you are seated and remain as still as possible. There will always be a monitor on duty if you need anything. Every hour, the monitor will remind you to stand up, stretch, and walk for about two minutes. They will also give you a sheet of paper to take notes about your activity so you can replicate it to the best of your ability on your second visit. To exit the chamber, all you have to do is turn a big red button, and there’s an arrow pointing to it on the wall. Plus, there’s a window inside the chamber that faces the outdoors. No need to get claustrophobic!

View of the chamber from the entrance.

The monitors serve you breakfast, lunch, and dinner, with a snack in between lunch and dinner. Don’t worry at all about getting hungry – the meals provided are tasty and filling. Plus, thanks to the metabolic chamber providing live data, the staff know your calorie needs at all times.

If it’s your exercise day, you’ll run on the treadmill around mid-morning. You rest for 45 minutes after the exercise, then you use sanitary wipes to feel clean again, and you can change into clean scrubs. If the study requires you to take supplements or provide blood samples, the monitors will tell you what to do. In the chamber, there are two intercoms that you can use to communicate with the monitor, one near the treadmill and one near the bed. There’s also a window where you can see the monitor, and a webcam so they can see you. Don’t forget – the toilet is not within view of the webcam and there is a curtain over the window. Your privacy is respected while you are in the chamber! The lights go out for “bedtime” at 10:00, and you sleep (or stay as still as possible when you’re awake) until 6:45 or so. You will be compensated well for your time, even if you complete just one visit.

In studies investigating exercise and energy expenditure, the second day is essentially the same as the first but with one key difference: on this visit you will spend 45 minutes on a treadmill, exerting yourself to 75 percent of your “V02 max,” the maximum amount of oxygen that you use during intense exercise (measured as milliliters of oxygen used in one minute per kilogram of body weight). Before you begin the study, they will test your V02 max by having you run on a treadmill at an incline. In the chamber on your exercise day, it’s a tough workout. But you can do it!

Metabolism studies are important because there is an obesity epidemic in the United States, caused by excessive calorie intake and a lack of physical activity: 69 percent of adults are overweight, with a BMI of 25 or higher, and 35 percent of adults are obese, with a BMI of 30 and higher. Obesity increases the risk of a variety of conditions that are linked to heart disease, including high blood pressure, diabetes, and high cholesterol. Heart disease is the leading cause of death for men and women worldwide.

So by studying the human metabolism, researchers from ASU and the NRI also want to help people effectively and safely lose weight to reach a healthy weight, lowering their risk of heart disease and other complications. Here a few simple recommendations:

  • Eat more carbohydrates and dietary fiber from whole grains
  • Eat more fruits and vegetables
  • Eat less fat to reduce overall caloric intake
  • Engage in physical activity most days of the week, with a total of 150-300 minutes per week

ASU and NRI experts have found that limiting calorie intake – eating less – has the biggest impact on weight loss. Exercise helps, but it must be more than 60 minutes per day to be meaningful. In other words, physical activity is more important for improving health (a good thing!) than for accelerating weight loss.

Sources: UNC Nutrition Research InstituteAmerican Heart AssociationASU Human Performance Laboratory

To Supplement or Not to Supplement: That Is the Question

TIME reported on a new study this week that ultimately concluded that taking nutritional supplements is not the same as eating a healthy diet. Researchers report that you cannot be truly healthy without getting your nutrients from the source – from fruits, vegetables, and other plant-based foods.

My first thought: We call them “supplements” for a reason, right? They are intended to be “supplemental” to a mostly healthy diet. They are “supplements” not “replacements.”

A second thought: Not all supplements are created equal. I’m certainly not an expert on what makes a nutritional supplement effective or not, and I’m not sure how the scientists from this study qualified a “supplement,” but I do feel compelled to mention briefly the philosophy behind the nutritional supplements produced at Standard Process, my current employer.

An SP Aside

Standard Process produces nutritional supplements using ingredients from their organic farm in Palmyra, Wisconsin. Unlike other supplement companies, they boast a whole-food philosophy. This is based on the science of a whole food matrix, the idea that macronutrients (fat, carbohydrate, protein), micronutrients (vitamins, minerals), and phytonutrients (carotenoids, resveratrol, etc.) are the most bioavailable/biologically active/effective when they are consumed in the natural “matrix” in which they are found in nature. This separates Standard Process and other companies with a similar whole food philosophy apart from supplement companies that simply extract vitamin D or beta-carotene and insert them into a capsule to sell as a supplement.

That being said, I should clarify that my personal philosophy is food first, supplements second (if at all). We may not know for sure what types of supplements are most effective or if any are effective at all at improving nutrition, but you certainly can’t go wrong with getting your nutrition straight from the source (plant foods).

Okay, let’s talk about this new research.

TIME reporter Jamie Ducharme begins the story with two important facts:

I think it’s fair to extrapolate from those two statistics that many of those 90% of Americans that do not eat enough fruits and vegetables are among the 75% who are taking dietary supplements, likely because they know that they aren’t getting enough nutrients from their diet. Fair – it’s certainly easier to pop a pill than to get enough servings of leafy greens every day, but those 75% might be wasting their money on supplements that aren’t giving them the nutrition they really need.

The Study: Annals of Internal Medicine

The study’s main point is this: “nutrients consumed via supplements do not improve health and longevity as effectively as those consumed through foods.” Pretty simple. Supplements are not as good as food. Anyone surprised?

More specifically, researchers report that nutrients consumed through supplements are not as strongly associated with living a longer life as nutrients consumed through food. The data comes from the National Health and Nutrition Examination Survey (NHANES) 1999-2010, including 30,000 American adults as participants who were followed for about six years (at the end of this period, there were more than 3,600 deaths).

Researchers factored in monthly supplement use and dietary habits when establishing nutrient levels for each participant. This data initially led them to the result that dietary supplements are associated with a lower risk of early death, but that result did not hold true with researchers factored in certain other details about the participants: education levels, socioeconomic status, and demographics. After controlling for these variables, researchers found that it was mostly the higher-income and better educated people who were taking supplements, and this group is on average more likely to be healthy anyway. Put another way: for this group, it wasn’t supplement usage that was improving health, it was the impact of wealth and education on health (another story for another day).

The study showed that sufficient consumption of micronutrients like vitamin A, vitamin K, magnesium, zinc, and copper are associated with a lower risk of dying early, but only when obtained from food – not supplements.

Researchers even mentioned potential negative health associations with supplement usage. For example, high doses of calcium via supplement was associated with a 53% higher risk of dying from cancer compared to people who did not take supplements. Excess calcium from food did NOT have that association.

Regulatory Considerations

I think it’s important to note that the Food and Drug Administration (FDA) not does not regulate nutritional supplements as tightly or in the same way as “conventional” foods and drugs are regulated. Whether it’s safety or efficacy that one is worried about, the regulatory difference is a significant factor.

Supplements for Specific Populations

Lastly, I’ll highlight that the study scientists did mention that nutritional supplements may provide positive health benefits particularly for two groups:

  • The elderly: because the ability to absorb nutrients from food can decrease with age
  • People with dietary restrictions (allergies, vegan, vegetarian, etc.): because they are more likely to have nutrient deficiencies from lacking certain foods

Take-home Points

  1. While I acknowledge that it’s certainly easier said than done (I struggle in my own life), I agree with study co-author Fang Fang Zhang (Tufts University Friedman School of Nutrition Science and Policy) when she recommends that instead of relying on nutritional supplements, people should just eat a healthy diet rich with fruits, vegetables, and whole grains.
  2. There’s always more to the story. That’s why I included my SP aside earlier. The conclusion is never going to be “all supplements are bad” or “all supplements are good.” There are so many factors that affect what makes an effective nutritional supplement, and the only way to truly determine what’s effective and what’s not is to follow reputable research like this study from Zhang and others at Tufts University.

History of Dietary Recommendations in the United States

In some shape or form, as early as the 19th century Americans have been making dietary recommendations and heeding advice provided by experts.

Early 20th Century

Chemist Dr. Wilbur Olin Atwater’s 1904 publication “Principles of Nutrition and Nutritive Value of Food” was based on:

  • Variety
  • Proportionality and moderation
  • Measuring calories
  • An efficient, affordable diet focusing on nutrient-rich foods and less fat, sugar, and starch

Soon after the initial discovery of individual vitamins in 1910, nutritionist Carolina Hunt’s 1916 “Food for Young Children” created new categories: milk and meat, cereals, vegetables and fruits, fats and fatty foods, and sugars and sugary foods.

Mid-20th Century

The first Recommended Dietary Allowances (RDAs) were created in 1941 for calories, protein, iron, calcium, and vitamins A, B1, B2, B3, C, and D. RDAs are now defined as the “average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%-98%) healthy people.” The Food and Nutrition Board of the National Academy of Medicine also defined “adequate intake” (AI; “established when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy”) and “tolerable upper intake level” (UL; (maximum daily intake unlikely to cause adverse health effects”).

From 1943 to 1956, the United States Department of Agriculture (USDA) introduced the “Basic 7” a nutritional guide devoted to maintaining standards during wartime food rationing:

  • Green and yellow vegetables
  • Oranges, tomatoes, grapefruit, cabbage, salad greens
  • Potatoes and other vegetables and fruits
  • Milk and dairy products
  • Meat, poultry, fish, eggs, beans, peas, nuts, peanut butter
  • Bread, flour, cereals
  • Butter and fortified margarine

Late 20th Century

The list was condensed down to the “Basic Four” between 1956 and 1992:

  • Vegetable and fruits: 4+ servings recommended daily
  • Milk: 4+ servings for teens and 2+ for adults
  • Meat: 2+ servings
  • Cereals and breads: 2-4 servings

In 1992 came the Food Guide Pyramid, with a particular focus on expressing the recommended servings of each food group based on their location within the pyramid. The first version of the infamous pyramid-shaped chart featured fruits and vegetables as the biggest group. But pressure from the grain, meat, and dairy industries led to the final version of the chart featuring brain, cereal, rice, and pasta as the foundation of the pyramid. The Food Guide Pyramid was replaced with “MyPyramid” in 2005, which reverted to colorful vertical wedges and a running ascending the stairs to highlight the importance of exercise.

21st Century

The USDA’s current nutrition guidelines take the form of “MyPlate” – an initiative which began in 2011 and concentrates on five key food groups:

  • 30% grains
  • 30% vegetables
  • 20% fruits
  • 20% protein
  • Small portion of dairy

Additional recommendations include:

  • Portion control
  • Eat whole grains
  • Drink fat-free or low-fat milk over full-fat milk
  • Eat less sodium
  • Drink more water and less sugar-sweetened drinks

Key criticisms of MyPlate stem from the fact that the chart does not highlight plant sources of protein like beans and nuts. A similar but more plant protein-centric chart is Harvard’sHealthy Eating Plate,” which was created in response to deficiencies identified in MyPlate.

This century-long saga of changing recommendations depicts the fickleness of nutrition science and the unfortunate influence of the food industry on governmental dietary recommendations. We’ll never know the full story, but it is likely that nutrition experts in the early nineties involved in developing the Food Guide Pyramid knew full well that the bulk of your plate should be green (i.e. veggies) and not tan (i.e. bread and pasta). But influence from other food industries kept the Food Guide Pyramid from being 100 percent reliable. Who knows how this affected the obesity epidemic that currently plagues our country…

I hope you’ll excuse my rant and accept assurance that I am of course aware that there are a lot of other factors exacerbating the issue of obesity (processed food, fast food, sedentary living and working, etc.). None of us were “in the room where it happens” back in the early nineties (yes, that’s a Hamilton nod), so we can’t say for sure why the Food Guide Pyramid was developed in the way that it was. I also think I’m particularly sensitive about this era of government dietary recommendations because this is the guide that I grew up with, and it was the first major educational exposure I had to what a healthy diet looks like.

All in all, I do think that MyPlate is a great tool and shows that nutrition science (and the USDA) are moving in the right direction. My hope is that nutrition science and governmental recommendations will only get better and more accurate. Plus, did you hear about recent legislation proposed by democratic Congressman Tim Ryan to create a National Nutrition Institute under the National Institutes of Health? So cool.