Welcome to the HPRC Blog. We've got lots of information here, from quick tips to in-depth posts about detailed human performance optimization topics.
HPRC Fitness Arena: Nutrition
Wheat products such as bread and pasta are mainstays of our diets. However, some people are sensitive to gluten, a blend of two proteins found in wheat and other grains such as rye and barley. Three distinct conditions caused by gluten sensitivities have been identified: wheat allergy, celiac disease, and non-celiac gluten sensitivity.
Wheat allergy is more common in children than adults, and many children outgrow the condition. Symptoms include hives, itchy throat or eyes, and difficulty breathing. Wheat allergy can be life threatening and requires immediate medical attention—an especially serious consideration for Warfighters in the field.
Celiac disease is an autoimmune disorder that affects the small intestine. When a person with celiac disease eats foods containing gluten, his/her immune system attacks the small intestine, impairing the way the body digests food. Symptoms include bloating, gas, diarrhea, abdominal pain, lactose intolerance, and anemia. If not treated, celiac disease can cause neurological disorders, osteoporosis, and other autoimmune disorders such as type 1 diabetes. About three million people in the U.S. have celiac disease.
In non-celiac gluten sensitivity, or NCGS, a person is sensitive to gluten but—as the name suggests—does not have celiac disease. Symptoms include diarrhea or abdominal pain and vague, non-intestinal symptoms such as bone or joint pain, leg numbness, or skin rashes, making diagnosis difficult. About 18 million people in the U.S. have NCGS.
The only way to treat gluten sensitivities is to adhere to a strict gluten-free diet. Things to avoid include:
- Wheat, rye, and barley
- Flours made from wheat: self-rising flour, graham flour, cake flour, pastry flour
- Oats, unless certified gluten-free
- Communion wafers and matzo
- Soy sauce
Even if a product label says it is “wheat free” it might contain rye or barley. FDA has established guidelines for labeling gluten-free foods.
Gluten-free foods can become “contaminated” with gluten in home kitchens, so be sure to use clean tools for preparing and serving gluten-free foods, and designate appliances, such as a toaster, for use with gluten-free products only.
Many people with gluten sensitivities are deficient in calcium, folate, iron, and certain B vitamins. They should have their vitamin and mineral status monitored by a doctor.
Although following a gluten-free diet can be challenging at first, with a little practice it can become second nature. There are many gluten-free products on the market and many bakeries now offer gluten free selections. People who follow the diet typically experience significant improvements in their health and quality of life that make the effort worth the challenges. You can learn more about celiac disease and gluten-free diets from the Academy of Nutrition and Dietetics.
If there’s one constant in the military lifestyle it’s change. You could be engaged in a high-intensity ops tempo one day, and then find yourself at a desk job the next day (and vice versa). Similarly, you could be training for a triathlon, and then suddenly recovering from an injury. When your circumstances change, your calorie needs change too.
The Go for Green® plan is based on a Warfighter consuming 2,500 calories per day. Your needs might be different depending on a number of factors such as your age, sex, and level of activity. Go for Green® can help you choose appropriate foods for your calorie needs. But first, find out how many calories you need each day with this handy (downloadable, Excel) calculator from HPRC.
If your needs are greater than 2,500 calories per day—perhaps your job or workout regimen is very physically demanding—eating a few “yellow” foods (especially from the protein, fruit, and starchy food categories) and one or two “red” foods each day is appropriate for you. “Yellow” and “red” foods help boost the calorie content of your meals and restore your body’s carbohydrate and fat stores—essential fuels for Warfighters with high-calorie needs.
If your needs are less than 2,500 calories per day—maybe because you sit at a desk all day or you’re nursing an injury—it’s important to remember that reduced physical activity means reduced calorie needs. Steer clear of “red” foods and keep “yellow” ones to a minimum. Aim for plenty of “green” foods to help you heal and enhance mental and physical performance, and be sure to watch your portions to avoid unwanted weight gain.
And remember, “Green” foods are always a good choice for optimal performance, whatever your circumstances or calorie needs! For more information, visit the Warfighter section of the Go for Green® website and click on the “Personalizing G4G” tab.
A hot trend in nutrition and dieting for some Warfighters is internal cleansing (or “cleansing” for short). Typical cleansing programs promise renewed energy, weight loss, and a fresh start—appealing offers following the rigors of a deployment, a recent change of duty station, or just life in general. Variants of cleansing programs may include “detox” (short for detoxification) diets, dietary supplement products, enemas, or some combination of these.
Although some detox diets emphasize eating lots of fruits and vegetables and drinking plenty of water, many detox diets lack certain vitamins, minerals, and other nutrients, and are dangerously low in calories. It might be difficult for a Warfighter to obtain adequate calories for optimal performance while following a typical detox diet.
Detox supplement products often contain herbs and other plant-based chemicals that have a laxative effect. Long-term use of laxative products can cause changes in the structure of your large intestine (colon) that might have serious health effects. Laxatives can cause dehydration, which impairs performance. In addition, according to the Food and Drug Administration there are concerns about dietary supplement products containing hidden active ingredients that can result in harmful effects.
Detox enemas, often marketed as “colon cleanse” products, cause the contents of the colon to be quickly expelled. Detox enemas contain a variety of substances, some of which can cause allergic reactions or electrolyte imbalances. Since many detox enemas are self-administered, there’s also the risk of tearing the inside of your rectum during the procedure, which can cause septicemia—a type of bacterial infection in the blood.
The guiding principle behind cleanse programs is that environmental and dietary toxins supposedly build up in your body, and you need to get rid of them to be healthy. However, there really isn’t any scientific evidence backing up these claims. Your body is designed to detox itself by getting rid of wastes through urine, feces, and sweat. The best way to take advantage of these built-in detox systems is to drink plenty of water (to produce more urine), get plenty of fiber from fruits, vegetables, and whole grains (to help pass feces), and exercise (to produce sweat)—a proven program to help you perform better and live a healthy life.
Have you heard about Go for Green®?
Go for Green® is a DoD-wide, joint-service food-identification program. It’s designed to help you easily identify the nutritional value of foods when you’re standing in line at the dining facility (DFAC) deciding what to eat.
Foods in DFACs are color-coded Green, Yellow, or Red to help you choose foods for optimal performance. When using Go for Green® in the DFAC, look for these symbols to identify “Green,” “Yellow,” or “Red” foods.
What do the colors mean?
Go: High-Performance Food
“Green” foods can and should be eaten everyday. These foods score high in nutrient density (the ratio of nutrients to calories in a food) and help you perform best. Most “Green” foods can be eaten without having to worry much about portion size.
Caution: Eat occasionally
“Yellow” foods are still healthy in small amounts but should be eaten less often than “Green” foods. How much and how often depends on your health and performance goals. Try to eat “Yellow” foods just some of the time.
Limit: Eat rarely
“Red” foods are meant to be treats eaten just once in a while. They have little nutritional quality but are often an enjoyable part of eating. Most people can have a few “Red” foods each week and still meet health and performance goals. Try to limit how much and how often you eat “Red” foods, and balance them with plenty of “Green” foods.
Although the Go for Green® program is geared toward use in the DFAC, it translates well to just about any setting—home, fast-food restaurants, even when eating MREs. Eating the Go for Green® way can promote a healthier, better-performing you. For more information, visit the Go for Green® website. Download the Go for Green® Guide for a handy reference.
Need help deciding how much to eat? Look for future posts about how to personalize Go for Green® based on your individual calorie and performance needs.
Carbohydrates provide our bodies with energy. “Good” carbohydrates—usually the complex carbohydrates such as vegetables, fruits, and whole grains—have more fiber. They also contain vitamins and minerals. “Bad carbs” include refined carbohydrates—foods made with white flour—and processed foods with added sugars. To find out more about eating the good carbs, read the Centers for Disease Control and Prevention information on carbohydrates.
Warfighters who eat a variety of fruits and vegetables are more likely to be at their optimal weight and less likely to develop diseases such as cancer, heart disease, and diabetes. But it can be hard to find a “rainbow” of fresh foods when it’s cold and gray outside and the summer farmers’ markets and roadside stands are months away. Fresh fruits and vegetables, while a great choice, can be expensive in winter and can spoil quickly, making it hard to keep them on hand. Frozen fruits and vegetables, on the other hand, might be just the ticket to make sure you get plenty of these nutritious powerhouses in your diet. Here’s why:
- Nutrition. The nutrient content of frozen fruits and vegetables is comparable to that of fresh ones. That’s because frozen fruits and vegetables are processed at their peak ripeness, while fresh ones might be eaten when they are either under- or over-ripe, when nutrient content is generally sub-par. (There are a few exceptions, though. The processing of frozen “cruciferous” vegetables such as broccoli, cauliflower, and Brussels sprouts destroys important enzymes that give them their disease-fighting capability. Opt for fresh versions of these veggies, and steam them lightly or eat them raw.) When purchasing frozen vegetables, choose versions without added salt and with minimal processing such as chopping or dicing for highest nutritional value.
- Cost. Although fresh fruits and vegetables are usually cheaper when they’re in season, their frozen cousins are your best bet in the off-season. If you’re on a budget, resist the temptation to purchase those meal-in-a-bag concoctions containing meats and/or rich sauces, though. You pay twice: first for the convenience and second for the calories. Instead, prepare frozen veggies in your microwave according to the cooking directions on the package. If you add some lean protein such as chicken or tofu, some spices, and a side of whole grains, you’ll have the makings of a great meal.
- Availability. The best thing about frozen fruits and vegetables is that they’re right there in your freezer. You can stock up on your favorites when they’re on sale and have a ready supply every time you cook—no excuses. Use them within three months of purchase, though, for optimal quality.
Fresh or frozen, fruits and vegetables are essential for optimal performance. Be sure you get enough every day.
Wanting some holistic strategies to enhance your performance? Check out the “One Shot One Kill (OSOK) Performance Enhancement Program” that shows Warfighters how to set up and manage their own performance-enhancement system. OSOK is designed not only to enhance performance but also to jumpstart Warfighter resilience. It builds on the skills that Warfighters already possess and then teaches new ones as needed.
There are two ways you can use OSOK: as an individual through “OSOK Solo” and as a unit/group through “OSOK-IP Unit.” Both highlight “10 Rules of Engagement” and provide seven core modules: Controlled Response, Mind Tactics, Performance-Based Nutrition, Primal Fitness, Purpose, Code, and Recharge. OSOK also provides self-assessment forms so you can track your progress over time.
For other performance-enhancement programs and information about holistic (total) fitness, check out HPRC’s Total Force Fitness domain.
You may have heard about the Body Mass Index (BMI), but do you really know what it is? BMI is an indicator of body fat for most adults—a screening tool for possible health problems. BMI is calculated using weight and height, and depending on the number, the result is categorized into underweight, normal weight, overweight, and obese. The higher the BMI, the higher the risk of certain diseases such as heart disease, high blood pressure, Type 2 diabetes, and certain cancers. The Centers for Disease Control and Prevention has an adult BMI calculator, child and teen BMI calculator, and information for interpreting the numbers.
Do milk products make you queasy, gassy, or—worse—send you running to the bathroom? If so, you might have lactose intolerance, a condition caused by a deficiency of lactase, an enzyme produced in the small intestine. Lactase breaks down lactose, a naturally occurring sugar present in milk and milk products.
Symptoms of lactose intolerance include nausea, gas, cramping, and diarrhea and usually occur 30 minutes to two hours after eating milk products. Anyone (at any age) can develop lactose intolerance, but it’s more common among adults of African, American Indian, Asian, Jewish, or Mexican heritage. People who have digestive diseases such as Crohn’s disease, ulcerative colitis, or celiac disease are more likely to be lactose intolerant too.
Some people with lactose intolerance have to avoid all milk products, but others can handle small amounts of cultured milk products such as yogurt, kefir, or buttermilk. If you think you have lactose intolerance, experiment with milk products to see what you can handle.
Many processed foods (including MREs) contain milk products, so learn to be label-savvy: Look for words on food packages that indicate a product might have milk or milk products such as whey, curds, milk byproducts, dry milk solids, and nonfat dry milk powder. Missing your ice cream? Over-the-counter enzyme products can help you tolerate lactose-containing foods if taken with the first bite of food.
Don’t confuse lactose intolerance with milk allergy, an immune response to casein or whey, two proteins found in milk. Symptoms of milk allergy are typically mild and include:
- Runny nose, sneezing, or shortness of breath
- Swollen lips, tongue, or throat
- Rash, hives, or itchy skin
However, severe milk allergy can cause anaphylaxis, a serious, life-threatening condition that requires immediate medical attention. People with severe milk allergy should read labels carefully to avoid all milk products.
Of course, limiting or avoiding milk products could put you at greater risk of developing osteoporosis or “brittle bones.” That’s because milk products contain calcium, an essential nutrient for healthy bones. Look for other calcium-rich foods such as dark-green leafy vegetables, almonds, beans, shellfish, or calcium-fortified juices, soymilk, or almond milk.
To learn more about lactose intolerance, read this informative article from the National Digestive Diseases Information Clearinghouse.
There’s an old adage you may have heard: “Eat after eight, put on weight.” And maybe you’ve experienced it first-hand: You noticed that eating those late night pizzas and ice cream really packed on the pounds. But was your weight gain due to timing or just the high calorie counts? According to research in the field of circadian rhythms (CRs)—the 24-hour cycle of your body’s biological, hormonal, and behavioral patterns—it seems that when you eat could be just as important to weight gain as what you eat.
Deep within your brain sits a small cluster of nerve cells—a “master clock” of sorts—that’s responsible for orchestrating your CRs. Each biological system in your body works on a different CR schedule, and the master clock keeps all the schedules in sync. For example, CRs influence your body’s production of the hormones that regulate hunger, as well as how your body uses and stores fats and sugar, ultimately influencing your body weight, performance, and overall health. Other hormones, such as the ones that tell you when you’re full, are switched on or off according to a variety of inputs.
The two greatest influences on how well your master clock is able to keep things in sync are light and food. Light tells your brain how much sleep you get (think: eyes closed, less light). Food (smell, taste, and consumption) tells your body to produce a myriad of chemicals. As a result, staying up late at night, working shifts, and eating at all hours of the day and night—whether voluntarily or due to the demands of overseas deployments, training demands, shift-work schedules, and even parenthood—can play havoc with your circadian rhythms.
In an interesting twist, not only do CRs influence hunger and body weight, but excess body fat and/or a high-fat diet may disrupt CRs. This can lead to further weight gain, culminating in a collection of health problems known as “metabolic syndrome.” In the U.S., regular loss of sleep closely parallels the occurrence of metabolic syndrome. In addition, researchers have found that people who sleep less or have poor-quality sleep are more likely to become obese.
What to do? Make a conscious effort to “normalize” your daily routines as much as possible to maintain regular mealtimes. Whether you choose to eat three regular-sized meals or four to six smaller meals a day, space them out through the daylight hours to take advantage of your body’s natural rhythms. Here are some suggestions to avoid eating late at night:
- Try to eat a balanced dinner at least two hours before you go to bed, and take a walk afterwards when possible.
- Sip on soothing herbal tea or flavored water (without sugar).
- Be aware that watching TV (especially food-related ads) can trigger your desire to eat.
- Sometimes it can help to create new nighttime rituals that don’t involve eating, such as light stretching or yoga, taking a warm bath, listening to soothing music, or reading (or listening to) a book.
But if you find yourself up late at night—whether it’s due to a hard day at work, regular shiftwork, or temporary shifts due to jet lag or an infant’s night feedings—resist the urge to snack out of boredom or to “keep your energy up.” Shift workers should pack or purchase a healthy meal to eat during their work hours—one that includes lean protein and complex carbohydrates such as whole grains, fruits, and vegetables. Eat early in the shift if possible, so you’ll have the energy you need to think and move efficiently. Travelers and parents should look for healthy snacks that follow a similar pattern. And try to limit coffee, tea, and other sources of caffeine to just two to four servings a day.
Of course, eating is just one half of the CR equation. Getting enough sleep is important too, so read HPRC’s overview for great tips on how Warfighters can improve their sleep.