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HPRC Fitness Arena: Nutrition
The Paleo Diet, also known as the Paleolithic or Caveman Diet, is based on the notion that by consuming what humans ate during the Paleolithic Era—wild animals, plants, eggs, tree nuts, vegetables, roots, fruits, and berries—we will be healthier, have lower disease risk, and live longer. Hunters/gatherers during that time had to rely on what was available and had no agriculture. But what are the implications of this type of diet for the athlete, let alone the average individual?
Foods that were grown and introduced after the Agricultural Revolution (roughly 10,000 years ago) are not allowed in the Paleo Diet. That means dairy and dairy products, grains, and legumes (beans, peas, and lentils) are excluded. Proponents of the Paleo Diet believe that we are “genetically programmed” to follow the diet of the hunters/gatherers. A specific book has been written for athletes who want to follow this diet, which accommodate athletes by allowing some carbohydrates: The authors present five stages of eating for the athlete to follow, based on the glycemic index (GI; how quickly food raises blood glucose levels). The stages are: (1) eating before exercise, (2) during exercise, (3) and 30 minutes after exercise, and (4) during post-exercise extended recovery and (5) long-term recovery. Low- to moderate-GI carbohydrates are recommended at least two hours prior to exercise. Sports drinks or high-GI carbohydrates are recommended for exercise lasting longer than 60 minutes. Immediately after exercise a recovery drink with carbohydrate and protein in a 4:1 to 5:1 ratio is recommended. Stage IV recovery foods (extended recovery) should be a 4:1 to 5:1 carbohydrate-to-protein ratio, with carbohydrates such as raisins, potatoes, sweet potatoes, and yams. Stage V recommends focusing on eating from the main Paleo Diet, with carbohydrates coming from fruits and vegetables. So one could argue that the Paleo Diet for Athletes is like most diets for athletes in that it requires carbohydrates. However, the Paleo Diet for Athletes is higher in protein and fat and lower in carbohydrates than what is recommended for athletes by most health professionals.
What we do know from scientific research is that carbohydrates provide the energy needed for endurance and resistance training, competitive athletic events, mental agility, and healthy living. Complex carbohydrates such as fruits, vegetables, whole-grain pasta, rice and grains, beans, and other legumes contribute to an overall healthy eating plan. By limiting consumption of some of these to only a brief time after exercise, the athlete runs the risk of not having enough fuel for the body, so the body will use protein for energy. Low-fat dairy products also contribute to a healthy lifestyle, providing much-needed calcium and vitamin D as well as probiotics. The Paleo Diet eliminates dairy entirely, even for athletes.
We also know from the scientific literature that during the post-exercise period, within roughly 30-45 minutes of exercise, eating a carbohydrate/protein snack, generally with a 3:1 carbohydrate-to-protein ratio, is essential to stimulate re-synthesis of muscle proteins and replenish glycogen (the storage form of carbohydrate). It doesn’t stop there: It is important to maintain glycogen levels in the muscle and liver to sustain all activities, especially over the course of several days. Eating high-carbohydrate snacks between training sessions is important to replenish glycogen stores. Carbohydrate intake recommendations for athletes are 6 to 10 g/kg body weight per day, or roughly 55% of daily calories from carbohydrates.
What’s the bottom line? Grains and dairy products are staples of modern-day society and provide essential nutrients to an overall healthy diet. By eliminating one or more food groups, you run the risk of missing important nutrients. And can we really eat as humans did during the Paleolithic era? Their life expectancy was about one quarter to one half of what ours is, and we benefit from research showing that eating a variety of foods over the course of time provides us with energy and the important vitamins and minerals needed to sustain us in daily activities and exercise.
The Department of Defense (DoD) Combat Feeding Program (CFP) is responsible for all of the combat rations that feed service members and for the research, development, engineering, integration, and technical support of those rations. Their mission is to ensure that United States Warfighters are the best-fed in the world. It’s important that any new combat ration developed is fueled by the wants and needs of Warfighters themselves; they even field-test new rations to make sure that their requirements are being met. Items that pass their standards are then incorporated into ration menus so that they have a variety of nutritional meals to choose from.
The Meal, Ready to Eat™ (MRE™) is used by all military services to feed Warfighters during operations where food service facilities are not available. MREs are essential to military subsistence; they’re intended to provide a Warfighter’s sole sustenance for up to 21 days of deployment (in accordance with AR 40-25) and are still nutritionally adequate for longer periods if necessary. MREs™ are shelf stable for 36 months at 80˚F.
The Unitized Group Ration – Heat & Serve™ (UGR-H&S™) is designed to feed 50 Warfighters per module and is the first group meal consumed in early deployment, as soon as field kitchens (without refrigeration capability) are available. All components of the ration are pre-cooked and shelf stable for 18 months at 80˚F.
The UGR-A™ is also designed to feed 50 Warfighters per module and consists of high-quality group meals. The UGR-A™ is the only military operational ration that contains frozen food components. It’s based on a build to-order assembly process that requires refrigerated/ frozen storage and a field kitchen for preparation.
The UGR-B™ is used primarily by the Marine Corps to provide high-quality group rations that don’t require refrigeration and are quick and easy to prepare.
The UGR-Express™ (UGR-E™) is designed to provide a complete, hot meal for 18 Warfighters in remote locations where group field feeding wouldn’t be possible otherwise. It’s a compact, self-contained, self-heating module that doesn’t require cooks or a field kitchen for preparation. With the simple pull of a tab, the food is heated in 30-45 minutes and is served in trays to Warfighters like a cook-prepared meal.
The First Strike Ration® (FSR™) is a compact, eat-on-the-move assault ration intended to be consumed during initial assault by forward-deployed Warfighters. The FSR™ is shelf stable for 24 months at 80˚F and provides a new capability in that it is 50% lighter, smaller, and easier to prepare when compared to the MRE™.
The Meal, Cold Weather™ (MCW™) and Food Packet, Long Range Patrol™ (LRP™), which contain freeze-dehydrated entrees, are designed to meet the nutritional and operational needs for extreme cold environments, special operations, and long-range reconnaissance missions. They are shelf stable for 36 months at 80˚F.
The Modular Operational Ration Enhancement™ (MORE™) is an enhancement pack designed to augment operational rations with additional calories and nutrients when Warfighters are operating in extreme environments such as high altitude in cold or hot weather.
For more information on any of the above, please call (508)-233-4670 or visit the Army’s Natick Soldier Research website.
A myriad of dietary supplements make their way to the market labeled as “healthy” for the public. However, many contain dangerous substances, including steroids, and consumers have no idea they are taking harmful substances. Supplement Safety Now, a public protection initiative, was founded by the U.S. Anti-Doping Agency to make sure over-the-counter supplements are safe for consumers. For more information, read more about this initiative.
Salmon is commonly touted for its omega-3 fatty acids. HPRC recently received a question about what foods other than salmon are the best sources of omega-3 fatty acids. For a complete answer, including the recommended intakes from the American Heart Association, please see HPRC’s answer.
Many adverse events associated with dietary supplement use go unreported. HPRC has developed one page information resources on how to report adverse events. Warfighters and their families can follow the directions for reporting adverse events to MedWatch (FDA) and Natural Medicines Watch. In addition to these sites, Health care providers can follow step by step directions for reporting via AHLTA.
Recently there has been a multistate outbreak of listeriosis from cantaloupes. The Centers for Disease Control and Prevention (CDC) has an informative report about listeriosis, including symptoms, food contamination, and how to take steps to avoid this serious infection.
Apple juice containing arsenic has been a topic in the news recently. The Food and Drug Administration (FDA) has put together questions and answers to assist the public in sorting through the information. The FDA’s conclusion is that apple juice is safe to drink. More information is available in FDA: Apple Juice Safe To Drink.
Apidexin is a weight-loss supplement that contains vitamin B12, chromax (a form of chromium), and a proprietary blend of various ingredients. One of the ingredients is guggul, which has been associated with side effects such as headaches, nausea, vomiting, diarrhea, skin reactions, and more. Other ingredients in Apidexin with known side effects are Irvingia gabonensis and DiCaffeine Malate. Both been associated with headaches and difficulty sleeping, and the latter also can increase heart rate and raise blood pressure. And keep in mind that there’s no data on how all of these ingredients might act together. For more detailed information, read HPRC’s Answer to a recent question about the side effects of Apidexin.
Vitamin C is a nutrient found in citrus fruits, broccoli, strawberries, cantaloupe, tomatoes, other fruits and vegetables, as well as fortified 100% fruit juices. Among other things, it acts as an antioxidant, helping to protect cells from damage caused by free radicals, which your body produces as it converts food into energy. How much you need depends on your age. For the average recommended daily amounts and other information about vitamin C, read the Office of Dietary Supplements Quick Fact Sheet.
Looking for programs to help manage your weight? The Human Performance Resource Center just posted its new “Fighting Weight Strategies” page, where we have compiled a list of programs and resources, arranged by service, for maintaining overall health and body weight. You can find these helpful resources by going to the Fighting Weight Strategies page of HPRC’s website.