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
Grapefruit is a tropical fruit known for its lip-puckering flavor. It contains vitamin C and many other nutrients and is a regular feature at the breakfast table. Grapefruit and its extracts also show up as flavoring agents in beverages and are sometimes added to dietary supplements.
Despite its many health benefits, grapefruit can pose a risk for people taking certain drugs. That’s because grapefruit can affect the way drugs are broken down or transported in the body—potentially increasing or decreasing the drugs’ effectiveness.
If you enjoy eating grapefruit or grapefruit-containing products, be aware of potential interactions when taking medication. If you take prescription or over-the-counter drugs, ask your doctor or pharmacist if you should avoid grapefruit. This consumer update from the Food and Drug Administration has more information.
Sodium—a component of table salt—is an essential element. It helps your muscles and nerves function correctly and maintains the proper balance of your body’s fluids. However, too much sodium in your diet may increase your risk of high blood pressure, heart attack, stroke, and certain types of cancer.
The average American consumes about 3,400 milligrams (mg) of sodium every day, mostly in the form of salt. But the current Dietary Guidelines for Americans recommends that adults limit their sodium intake to just 2,300 milligrams per day—roughly the amount in one teaspoon of table salt.
The guidelines also recommend that certain “at-risk” groups limit their sodium intake to about 1,500 mg per day: adults over the age of 51, African Americans, and people who have high blood pressure, diabetes, or kidney disease.
Recently, the Institute of Medicine (IOM) looked at the evidence supporting the current recommendations regarding sodium intake. IOM concluded:
- Research supports current recommendations to reduce sodium intake to about 2,300 mg daily.
- More research is needed to support the recommendation that those “at risk” should cut back to 1,500 mg or less a day.
Bottom line? If you’re in an at-risk group, speak to your doctor or registered dietitian about whether you should reduce your salt intake. For just about everyone else: Cut back on the salt.
How? Most of the sodium Americans consume comes from processed foods—tomato sauce, soups, canned foods, bread, and prepared mixes—but it can also come from foods naturally high in sodium—cheese and some types of seafood. Also, many restaurant foods are high in sodium, but sometimes you can request low sodium items. The best way to ensure a low sodium diet is to eat whole foods such as fresh or frozen fruits and vegetables; lean, unprocessed poultry and fish; unsalted nuts; whole grains; and low-fat dairy products such as skim milk or yogurt. For more information, check out this CDC web page.
For additional information and other conclusions from the study, see the news release (which includes a link to the full study) from the National Academies.
Sugar can be present in foods even when we don’t know it. Some hidden sources of sugar on listed food labels are high-fructose corn syrup, brown rice syrup, brown sugar, honey, maple syrup, glucose, (or dextrose), lactose, sucrose, and the sugar alcohols sorbitol, zylitol, mannitol, and maltitol. Those people watching their sugar intake should read labels carefully to spot hidden sources.
Tribulus terrestris is used as an ingredient in some dietary supplement products marketed as testosterone “boosters” and/or to enhance muscle strength. What is it and does it work? Read this OPSS FAQ about Tribulus terrestris to find out. Also, be sure to check the OPSS section often, as we add answers to other questions about ingredients in performance-enhancing and bodybuilding supplements. OPSS can help you learn how to choose supplements safely.
If you have a question about a particular dietary supplement ingredient or product, and you can’t find the answer on our website, please use our “Ask the Expert” button located on the OPSS home page.
Do you know that many kinds of chewing gum—including the gum in MREs—contains a sugar sweetener called “xylitol”? This natural sweetener can be good for your teeth and gums! Xylitol has been found to offer preventive dental benefits, including reduced bacteria and acids that cause cavities and significant decreases in plaque. Most studies have shown that the use of chewing gum or mints with xylitol three to five times a day, especially after eating, result in the greatest benefits. Other sugar-free sweeteners used in gum and mints offer some oral health benefits, but for maximal benefits use products with xylitol. For more information, read this health fact sheet xylitol and how it can protect your teeth. Although chewing gum or mints with xylitol helps reduce cavities, they do not replace the benefits of regular brushing and flossing.
Operation Live Well is a new wellness campaign by the Department of Defense that aims to make healthy living the easy choice and the norm for service members, retirees, DoD civilians, and their families. They point out resources for how to eat better, stay physically active, quit or avoid tobacco, and stay mentally fit. The educational, outreach, and behavior-change initiatives provide tools and resources to help you learn about healthy lifestyles. You’ll also be able to develop your own personalized health plan via the Operation Live Well website soon.
A second part of Operation Live Well is their Healthy Base Initiative (HBI), which aims to help the defense community reach or maintain a healthy weight and avoid tobacco use. Scheduled for launch during the summer of 2013 at 13 military installations and DoD sites worldwide, HBI will offer a range of installation-tailored, health-related programs that will be measured for their effectiveness. The programs that are most successful will eventually be expanded to other installations.
For more information on Operation Live Well, visit militaryonesource.mil/olw.
June is National Fresh Fruits and Vegetables Month. And it’s no wonder—during the warm summer months many fresh fruits and vegetables are at their peak. So take advantage of nature’s bounty and make an effort to include more fruits and vegetables into your family’s diet. Here are some tips to help:
- Start early: Top your morning breakfast cereal with fresh berries, bananas, or peaches for added flavor and nutrition.
- Add some crisp lettuce leaves and juicy tomato slices to a sandwich or wrap.
- Kids love foods they can “dip,” so encourage them to dip their veggies in a delicious, healthy fresh tomato salsa.
- Keep fresh veggies and fruits on a platter in the refrigerator so kids (and you!) can grab some any time—cooling off by the pool, reading a book, or cooking dinner.
- Go to a farmers’ market to find the freshest, in-season produce.
- Plant your own garden—or just a small tomato plant on the back porch. There’s nothing quite like homegrown fruits and vegetables.
- Have some dessert! Fruits are full of natural sweetness—the perfect way to round out a meal.
Eating fruits and vegetables may reduce your risk of cancer, diabetes, and many other diseases. To find out how many fruits and vegetables you and your family should be eating, use this great calculator from the Centers for Disease Control and Prevention. The U.S. Department of Agriculture has more information about the benefits of eating fruits and vegetables as well as lots of great tips to help you incorporate fruits and vegetables into your diet.
Cheeba Chews are marketed as chocolate taffy, but they actually contain an illegal substance. Read the Operation Supplement Safety (OPSS) FAQ to find out more about these products and whether they are legal for members of the military community to consume. Be sure to check back often as we add answers to other questions and topics in the OPSS section of HPRC’s website.
The purpose of the 2011 Department of Defense Health Related Behaviors Survey of Active Duty Military Personnel (HRB) is to assess the health practices of active-duty service members. Substance abuse, mental and physical health, and lifestyle choices are important matters, especially when you need to be at your best for the demands of military life. Certain areas of this study directly affect human performance, and results (as reported in the Executive Summary) show that health behaviors vary between services.
Physical Activity/Body composition
Here are some figures from the Physical Activity/Body Composition portion:
- Overall, service members have lower rates of obesity (as defined by BMI) compared to the general public.
- More than one-third of active-duty service members age 20 and older were considered to be at a healthy weight, which exceeds the Healthy People goal as well as civilian population estimates.
- 75% of active-duty members practiced moderate to vigorous physical activity in the 30 days prior to the survey, with Army and Navy personnel having the highest rates.
- Almost half of service members do strength training three or more days a week.
Physical health and fitness are key components to optimal fitness. While these numbers are encouraging, there is no doubt that a larger portion of the military should be at a healthy weight and fit enough to fight. Make fitness and weight management your priority for performance.
- Only 40% of all active-duty personnel surveyed get the recommended seven to eight hours of sleep per night.
Sleep is an important factor in recovery. Poor sleep habits can take a physical and mental toll on your health, your relationships, and your performance.
Tobacco and alcohol
One area where the military could improve is in the use of tobacco products and alcohol:
- Almost one-quarter of service members reported smoking a cigarette in the 30 days prior to taking the survey, which is higher than the civilian population and the Healthy People objective.
- Smokeless tobacco use is also prevalent in the military with 12.8% of all service members using smokeless tobacco in the month leading up to the survey.
- Rates of binge drinking were higher in the military than in the civilian population and more prevalent in the Marine Corps than in any other branch.
Tobacco in any form is detrimental to your health. If you’re thinking about quitting smoking or would like to talk to someone about your alcohol use, there are lots of resources and professionals that can help you achieve your goal.
Stress and mental health
After more than a decade of ongoing war, troops have—and will continue to experience—significant mental stress as a result of their service. In general, 5-20% of service members reported high rates of anxiety, depression, PTSD, and/or other mental health concerns.
- The most common military-related sources of stress were being away from family and friends and changes in workload but included financial problems and family members’ health problems.
- Women reported experiencing personal sources of stress more often than men did.
- Those who drank heavily were more likely to report problems with money and relationships.
Drinking, smoking, overeating, and even attempted suicide are all negative coping factors when dealing with stress. The survey found that the most effective methods of coping were planning to solve problems and talking with friends or family members. Find out how to use productive and effective methods for coping with stress and mental health.
Nutrition and dietary supplements
Being fueled to fight is an important component for anyone in the military. Proper nutrition requires consuming healthy—and avoiding bad and potentially harmful—foods and beverages.
- According to the survey, active-duty personnel eat too many unhealthy foods such as snacks, sweets, and sugary drinks and not enough of the recommended servings of fruits and vegetables.
- More than one-third of personnel reported daily dietary supplement use.
What you decide to put in your body now may affect your performance and your career later. For more information on nutrition for combat effectiveness, read Chapter 15 of the Warfighter Nutrition Guide. And make sure you know what you’re putting into your body. Dietary supplements are not subject to pre-market approval by the FDA, and there are many ingredients that may do more harm than help. You can learn more about dietary supplements at Operation Supplement Safety. And for more information about the Health Related Behavior Survey, visit TRICARE’s webpage.
Some recent evidence suggests that probiotic foods can contribute toward a healthy population of microorganisms in your digestive tract (gut). But what exactly are probiotic foods?
According to the World Health Organization (WHO), probiotic foods contain “live microorganisms which, when consumed in adequate amounts as part of food, confer a health benefit on the host.” In other words, they are foods that contain microorganisms (primarily bacteria and yeast) that may play a role in keeping the human gut healthy.
An astonishing number and variety of microorganisms—some good and some bad—occupy every nook, cranny, and passageway of our bodies. Most inhabit our digestive tract and play key roles in digesting food and digestive health. Maintaining the proper balance of good and bad organisms is essential. In fact, having more “bad” than “good” microorganisms is also associated with increased risk for short-lasting diseases such as colds and gastroenteritis and long-lasting diseases such as asthma and certain types of cancer.
More than 5,000 different strains of bacteria may reside in the average person’s digestive tract, which makes it hard to determine which ones might be good and which ones might be bad. But generally speaking, two strains seem to offer the greatest benefit to humans—Lactobacillus and Bifidobacterium. Both can be found in many widely available probiotic foods.
Fortunately, it’s easy to find probiotic foods these days. Take a walk down the dairy aisle of your local grocery store and you’ll likely find yourself inundated with products promising a variety of beneficial health effects, many of which are attributed to the products’ probiotic content. Choices include traditional fermented foods such as yogurt, kefir, and buttermilk as well as foods far from the dairy aisle such as sauerkraut, pickles, and miso (a soybean product).
Keep in mind that if you eat a greasy cheeseburger, fries, and a sugary soda followed by a yogurt “chaser,” it’s unlikely you’ll see much benefit from the probiotic organisms in the yogurt. The greatest benefits from eating probiotic foods occur when they are part of a diet that includes whole grains, plenty of fruits and vegetables, and low-fat sources of dairy and protein. For more detailed information, read “Oral Probiotics: An Introduction” from the National Center for Complementary and Alternative Medicine.