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HPRC Fitness Arena: Nutrition
Eating disorders require psychiatric, medical, and nutritional treatments and can have serious nutrition-related health consequences for a Warfighter, spouse, child, or an entire family. The cause of eating disorders is not well understood, but military members may be particularly susceptible due to the unique stressors associated with military life, and many military members with eating disorders may go undiagnosed. Treatment of eating disorders is complex and challenging. For more information, read HPRC’s InfoReveal on eating disorders.
Nutrition experts at the Institute of Medicine—or IOM—of the National Academies of Sciences gather extensive information to make nutrition recommendations for the American public. One major result is known as the Dietary Reference Intakes, or (acronym number one) DRI. You might come across some of the DRI’s acronyms when reading how to fuel your body or considering a dietary supplement, so it’s helpful to know what they mean and where they came from.
The Estimated Average Requirements (acronym number two: EAR) are the average amount of nutrients that half of all healthy people need each day. EARs differ depending on life stage and gender. Remember, though, they’re simply an average. Scientists use statistics based on this average to calculate the Recommended Dietary Allowances (acronym number three: RDA).
The RDAs are the daily nutrient goals for essentially all healthy people, again based on life stage and gender. For example, the RDAs of some nutrients (such as vitamin C) for a 13-year-old boy are very different from those for a 25-year-old pregnant woman.
The Adequate Intakes (acronym number four: AI) are the—you guessed it—adequate daily amounts of nutrients that healthy people of a particular life stage or gender need. AIs are given when there isn’t enough scientific evidence for a stronger recommendation, that is, an RDA. For example, the IOM suggests an AI for one type of omega-3 fatty acids—alpha linoleic acid—of 1.6 grams per day for men and 1.1 grams per day for women because scientists just aren’t sure yet how much is optimal.
Tolerable Upper Intake Levels (fifth and final acronym, for now: UL) are the highest daily amounts of nutrients that you can consume without risk of toxicity. Many vitamins and minerals—even essential ones—can be toxic when consumed in excess. For example, because too much vitamin A can cause liver damage, a UL has been established for this essential nutrient.
So, if you remember nothing else, remember to get your RDAs and AIs every day, but don’t exceed the ULs!
The USDA Food and Nutrition Information Center provides links to the DRI Tables, but generally speaking you can meet all your daily nutrient intake goals (the RDAs and AIs) by following a healthy diet that includes lean proteins, whole grains, fruits, vegetables, and low-fat dairy products. And be aware that recommendations do change. IOM reviews the most current nutrition science and updates the tables when necessary to keep up with the latest knowledge, which means better health for Warfighters and their families.
For optimal health and performance, Warfighters should try to eat at least six servings of vegetables (about three cups) every day. It’s tough, though, when you really don’t like vegetables. Here are some tips to help even die-hard veggie-haters work a few vegetables into their diets:
- Add vegetables to foods you already love! Macaroni and cheese, pizza, spaghetti sauce, soup, and omelets are great vehicles for spinach, broccoli, mushrooms, and other dreaded veggies. (Many of the vegetables in the MREs are hidden this way!)
- Grill your vegetables! Grilling adds those familiar flavors that we love so much. You can even baste them with your favorite low-fat marinade for extra flavor. Too cold to grill outside? Roasting vegetables in the oven makes many bitter-tasting vegetables taste sweeter.
- Drink up! You can find lots of tasty vegetable juices in grocery stores nowadays. Look for lower-sodium versions or the vegetable-fruit juice blends. You can even custom-blend your own by mixing bottled carrot juice with your favorite fruit juice.
- Get adventurous! Just because you hated something as a kid doesn’t mean you’ll feel the same way about it as an adult. Give vegetables another try—you might be surprised how tasty they really are.
Of course, these tips work for picky family members, too. How many vegetables should they eat? That depends—on their age, sex, and activity level. This chart from the USDA will guide you.
September is National Whole Grains Month! Whole grains are natural sources of vitamins, minerals, fiber, and other nutrients that are essential for good health. The Dietary Guidelines for Americans, 2010 recommends that at least half of your grain choices should be whole grains.
Try these tips to add more whole grains to your meals and snacks:
- Start with a hearty breakfast that features whole-grain cereals such as steel-cut oats, bran flakes, or shredded wheat. Eat breakfast on the run? Try switching to whole-wheat toast or whole-grain bagels instead of plain bagels. Substitute low-fat bran muffins for pastries.
- Lunchtime sandwiches using whole-grain breads or rolls are full of flavor and fiber. Swap out white-flour tortillas with whole-grain corn tortillas.
- Dinner sides can really shine when you replace white rice with exotic black or red rice or wheat bulgur. Add wild rice or barley to soups, stews, and casseroles. Whole-grain pastas give a nutty flavor to many dishes.
- Snacks can feature whole grains too: popcorn, graham crackers, or granola bars are tasty, healthy options.
- And don’t forget dessert: brown rice pudding, oatmeal cookies, or whole-wheat baked goods are just the ticket—wholesome and satisfying.
Remember, eating a variety of whole grains not only ensures that you get more health-promoting nutrients but also helps make your meals and snacks more interesting. The U.S. Department of Agriculture has more information about the health benefits of whole grains and even more tips on how to include them in your diet.
The Human Performance Resource Center is here to serve Warfighters and their families, commanders, and healthcare providers. If you’ve visited before, you probably know that we focus on “total force fitness.” But do you really know what that means—or how HPRC got started? If you’re curious, check out this PDF that describes HPRC, what we do, and the vast amount of information we cover. In addition, you may have noticed that we use the term “human performance optimization” throughout our site; this article also explains what that means.
The physical demands placed on the Warfighter in training and operational settings can take a toll on joints and bones over time. Following a healthy diet can help reduce your risk of many diseases and maintain healthy joints and bones. A few nutrients have been shown to support joint and bone health, including calcium, vitamin D, vitamin C, and selenium. Consuming too much alcohol has been shown to have a negative effect.
Calcium and vitamin D work together for strong bones and overall bone health, because vitamin D helps your body absorb calcium. Men and women ages 19–50 should try to get 1000 mg of calcium daily; older women need 1200 mg daily. Good sources of calcium include milk, yogurt, fortified orange juice, and green leafy vegetables. Your body produces vitamin D when your skin is exposed to sunlight, but you can also get it in your diet from salmon, tuna, and fortified dairy products. Adults need about 600 IUs of vitamin D daily.
Vitamin C is essential for cartilage—the material that cushions your joints and prevents bones from rubbing together. Men need about 90 mg and women need about 75 mg daily, roughly the amount in a large orange. You can get vitamin C from citrus fruit, broccoli, and tomatoes.
Dietary selenium (a mineral) also may play a role in bone health. Adults need about 55 mcg of selenium daily. Selenium is found in nuts (especially Brazil nuts), tuna, and sunflower seeds.
Drinking too much alcohol negatively affects many of the body’s systems, including the bones and joints. Alcohol can cause weight gain, increase risk for osteoporosis and stress injuries, and damage cartilage. Limit your alcohol consumption to one drink per day for women and two for men. A drink is defined as one 5 oz. glass of wine, one 12 oz. beer, or one 1.5 oz. shot of liquor.
Inflammation can play a role in joint conditions such as arthritis, so a diet that helps reduce inflammation might be beneficial in protecting your joints. Eating plenty of fruits and vegetables, whole grains, and healthy fats (found in nuts and fatty fish such as salmon) not only reduces inflammation, it can also help maintain a healthy weight, which is essential to preserving joint health.
Excess body weight stresses joints and increases wear and tear. Following a diet that is lower in fat and calories can help maintain or reduce body weight, preventing additional joint stress. For more information about healthy joints, read the fact sheet from the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Also, Chapter 17 of the Warfighter Nutrition Guide, “The High Mileage Warrior Athlete,” provides more information on maintaining joint and bone health.
The Department of Defense (DoD) Safety Review Panel published their findings on DMAA in a recent report now available through HPRC. The Assistant Secretary of Defense for Health Affairs asked the Safety Review Panel to evaluate the safety of DMAA-containing dietary supplement products. The Panel has recommended that the sale of DMAA-containing products be prohibited in all military exchanges.
HPRC maintains a list of dietary supplement products containing DMAA and periodically updates this list. The most recent version can be found on HPRC’s website. Note that, as of the FDA announcement in April 2013, DMAA is illegal in the U.S. as an ingredient in dietary supplements. For more information, visit the OPSS FAQ about DMAA. Operation Supplement Safety (OPSS) can provide service members and their families with information to make informed decisions about dietary supplement use. For the full DoD Safety Review Panel report, see the link on HPRC's Dietary Supplements web page.
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.