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HPRC Fitness Arena: Nutrition
Intermittent fasting has become a popular strategy for weight loss. “Fasting” can mean different things—from fasting as much as 16 hours per day to skipping or restricting caloric intake (for example, to less than 500–600 calories) one or two days a week. Fasting programs may make promises to their followers to lose weight and improve health, but are they safe and effective?
The health benefits claimed for intermittent fasting have mostly come from studies with animals. A few small studies with humans have shown intermittent fasting—eating as usual five days a week and eating 25% less two days per week—may be useful for weight loss. Because these studies were short term, however, the long-term safety and effectiveness of intermittent fasting are unknown.
In addition, it is unclear if intermittent fasting is more effective for weight loss than just eating less on a daily basis. Intermittent fasting could lead to overeating on non-fasting days, and even advocates of intermittent fasting point out that the key to weight-loss success is not to overeat on “normal” eating days.
Eating too few calories over time can result in low levels of vitamins, minerals, or other nutrients, and even the loss of muscle mass. And intermittent fasting can be dangerous for people with medical conditions such as pregnancy, diabetes, or eating disorders.
Common side effects of fasting include lack of energy, headaches, feeling cold, and constipation. Fasting can cause low blood sugar if you aren’t getting enough fuel to your brain, reducing your ability to concentrate and focus and affecting your sleep cycle and mood. These effects can interfere with your body’s ability to perform optimally.
Athletes who fast during Ramadan—a holy month when Muslims are expected to fast daily (no food or water) from pre-dawn prayer to post-sunset—provide some insights into the effects of fasting on performance. The limited intake of carbohydrates, protein, and fluid during fasting days sometimes affects their bodies’ ability to recover from exercise. Some found that their cognitive performance suffered as well due to the effects of even mild dehydration and inadequate carbohydrate intake. Exercise that is both physically and mentally challenging and long-lasting could have even greater negative effects.
Intermittent fasting may be unrealistic for long-term use. Reducing your overall caloric intake and a regular exercise program are the best combination for weight loss.
The holiday season is in full swing, which means an abundance of family feasts and holiday parties. But you can keep your nutrition in check and still eat balanced meals and snacks by practicing “mindful eating,” a form of mindfulness.
Mindful eating allows you to embrace food, nourish your body, and feel satisfied without overindulging. It means being more aware of your eating habits, eating cues, and sensations. When you eat mindfully, you learn to savor every aspect of your meal with all of your senses and become more conscious of your feelings of fullness. And while mindful eating isn’t a diet, it has been found to help with portion control and weight loss.
Try these mindful eating exercises before, during, and after your holiday get-togethers:
1) Recognize your feelings of hunger and fullness. Try to understand the reason you want to eat. Is it true physical hunger? Or do you tend to eat when your emotions are running high, such as when you’re stressed? Perhaps you saw or smelled something delicious, and all of a sudden your stomach is rumbling. Eat when you’re hungry. Don’t skip a meal just because you have a holiday party later in the day. If you wait until you’re starving, you might end up eating more than two meals’ worth. After you’ve had your first helping of food, wait about 10–20 minutes to determine if you’re still hungry or if you feel satisfied.
2) Savor your food. You can have your pumpkin pie and eat it too. Even calorie-rich foods can be eaten mindfully. First choose a sensible portion size. Then eat slowly, chew your food thoroughly, and put your fork down between each bite. Enjoy every taste, texture, smell, and sight of your food. Mindful eating also teaches us not to be judgmental about our food choices—there is no right or wrong way to eat!
3) Anticipate distractions and come prepared. People tend to eat more during social gatherings because there are more distractions and a greater number of food options. Be mindful of how your food choices nourish your body and support your health and well-being.
You can achieve healthy holidays by sticking to your eating plan and enjoying it too. All you have to do is retrain your brain!
There are various types of vegetarian diets, all of which exclude meat, while some also exclude fish, poultry, and other animal products. Although fruits and vegetables are rich in vitamins, minerals, and fiber, many of them are short on certain nutrients (such as protein). Being a vegetarian in the military can be challenging, but with proper planning—beginning with the right information from HPRC’s "Vegetarian diets - the basics"—a vegetarian diet can meet all of your nutritional needs.
Not only can plant-based diets be nutritionally complete, they also tend to be high in fiber and low in calories, saturated fat, and cholesterol. Thus, vegetarian diets offer a wealth of health benefits, including decreased risk for diabetes, heart disease, and obesity. As an added bonus, many vegetarian food options are considered “Green” foods under the Go for Green® program, which means you can eat these foods at every meal. Just be mindful of the amount of canned, fried, or dried (with added sugars) items you choose.
Weight-loss (diet) prescription medications are generally not permitted, but it’s important to check your service’s policy for specific conditions that may exist. Read this OPSS FAQ to find out more details, including links to specific policies. Also, be sure to check the OPSS site often, as we add answers to other questions about ingredients in performance-enhancing and bodybuilding supplements and how to choose supplements safely.
If you have a question about a particular dietary supplement ingredient or product, please use our “Ask the Expert” button located on the OPSS home page.
Do you know that one in six Americans get sick from foodborne illnesses each year? Thankfully, there are safety tips and techniques that can help you prevent such incidents. Here are some quick and easy tips to remember:
Clean: Wash your hands and surfaces thoroughly and frequently with hot, soapy water.
Separate: When shopping, preparing, and storing your meals, be sure to keep raw meats, poultry, seafood, and eggs away from other foods that won’t be cooked to prevent cross-contamination.
Cook: Use a food thermometer to ensure that your meats are cooked to the right temperature (165°F for turkey).
Chill: Don’t leave leftovers (including raw and cooked items, such as pies) out on the table for more than two hours. Promptly refrigerate these items, and use or discard leftovers within three to four days.
If food looks or smells questionable, a good rule of thumb to follow is, “When in doubt, throw it out.”
For more information on food safety, visit the Food and Drug Administration’s web page on Food Safety Tips for Healthy Holidays.
The Female Athlete Triad is a condition that commonly affects physically active girls and women, especially those involved in activities such as dance or gymnastics that have a heavy emphasis on weight and physical appearance. The Triad is characterized by energy deficiency, amenorrhea (menstrual disturbances), and osteoporosis (bone loss). Poor eating habits combined with high-intensity exercise can cause energy deficiency, although energy deficiency can occur even without disordered eating. Over time, estrogen decreases and causes menstrual cycles to become irregular or stop completely. However, estrogen is also important for building strong bones, so when estrogen levels drop, bones become weaker and osteoporosis can develop.
Female Warfighters can be at risk for developing the Triad if they don’t get enough calories and if training is too intense. In the short term, lack of energy will lead to fatigue and difficulty concentrating—an equation for poor performance. Continued energy deficiency, though, can lead to muscle loss and decreased strength, putting you at higher risk for injury. Then, even when you’re training hard, your performance may fail to improve or actually worsen.
You can prevent the Female Athlete Triad easily by focusing on your overall health and nutrition rather than your weight. Food is the fuel that helps you to perform at your best.
Cigarette smoking is the leading cause of preventable death and disability in the United States. The positive effects of quitting tobacco are numerous: Reduce your risk of lung and other cancers, improve wound healing, decrease risk of infection, and save money. However, a major concern among those who consider quitting tobacco is weight gain. Most people who quit tobacco gain less than 10 lbs, but others gain more than 20 lbs. Many factors contribute to this weight gain, including eating more due to improved sense of smell and taste, boredom, the need to do something with your hands, and metabolic changes that happen after nicotine leaves your body.
Being prepared is essential to preventing weight gain when you quit tobacco. Know your habits: If your hands will be bored without a cigarette, find something else besides food to occupy them. Play with stress balls, silly putty, crosswords, and puzzles to keep your hands busy. Dropping a bad habit such as smoking is also a great time to pick up something new to do with your hands: Knitting, playing an instrument, gardening, and writing are all healthy ways to exercise your hands and your mind.
If you’re craving snacks, reach for fresh fruits and vegetables. Fruits and vegetables are high in fiber and water, which help fill you up without a lot of calories. You may be confusing hunger with thirst; try a glass of water to see if that helps your cravings. Bored with plain water? Try calorie-free sparkling or seltzer water, or add lemon or lime slices, mint, berries, or cucumber to your water for a flavorful and refreshing drink.
And if you do find yourself eating more at or between meals, balance it out with exercise. Replace your usual smoking break with a walk outside or even around the office. Increase your usual gym routine; you may find exercise is easier after you quit tobacco.
For help quitting tobacco, or if you find yourself gaining weight no matter what you do, speak with your healthcare provider. And visit U Can Quit 2 and Tobacco-Free Living for additional information and resources. November is the Military Health System’s Tobacco Cessation month, so it’s a great time to make your own plan to quit tobacco.
Coffee, energy drinks, energy shots, soda—we’re surrounded by these products, and many are marketed specifically to teens. Their advertisements make caffeine seem a harmless and effective boost to help teens meet the demands of school and after-school activities. Three of four U.S. children and young adults now consume some form of caffeine every day.
Teens shouldn’t consume more than 100mg of caffeine (roughly the amount in an average small cup of coffee) per day. That’s enough caffeine to give you energy and help you stay alert. But too much caffeine can be a serious problem. Signs that you’ve had too much caffeine can be jitters, nervousness, increased heart rate, and an upset stomach. For more about the symptoms of too much caffeine, read FDA’s article.
Many drinks and foods that contain caffeine don’t clearly say so on the label. Energy drinks, for example, can contain lots of different forms of caffeine, such as guarana, green tea extract, and yerba mate. Although you might see these listed on the label, you still might not see the total amount of caffeine listed. Energy drinks don’t have to report how much caffeine is in them. So think twice about how many of them you drink, and learn more from HPRC’s article about energy drinks.
And for athletes: Don’t use energy drinks to replace sports drinks for extra energy. The same goes for other beverages with caffeine: sodas, coffee, and tea. Sports drinks are for hydrating and replacing electrolytes and other nutrients lost while exercising. Water is best in most cases!
Just because something contains caffeine doesn’t mean you have to completely eliminate it. Be aware of all the different sources of caffeine and try not to overdo it. And be sure to watch HPRC’s “Caffeine & Teens” video for more from a teenager’s perspective.
Based on a blog by HPRC intern Diana Smith. Diana is a military teen and high-school sophomore who is interested in science and enjoys drawing in her downtime.
Food and color additives exist in many of the foods that we eat. They are used to improve safety and freshness, maintain the nutritional value of foods, and improve texture and appearance. The Food and Drug Administration (FDA) has put together a helpful brochure reviewing how additives are approved for foods, types of food ingredients, and a description of food and color additives.
The month of October is Military Health System’s Women’s Health Month. There are more than 350,000 female members of the military (16% of the total military force). While it’s important for all military members to consume nutritious diets, women have special nutrient needs: iron, folic acid, and calcium.
Iron. Iron deficiency is the most common nutritional deficiency among women. Poor dietary intake of iron combined with intense physical activity can lead to fatigue, weakness, and pale skin—all signs of iron-deficiency anemia (IDA). Iron-rich foods include meat, poultry, fish, spinach, beans, and fortified cereals. Consume these foods with vitamin C–rich foods such as strawberries and oranges for better iron absorption. HPRC discusses other reasons for IDA in this article on “Iron deficiency.”
Folic acid. Women of childbearing age need enough folic acid to reduce the risk of birth defects. But even if you’re not pregnant, folic acid helps make blood cells that boost your immune system. Folic acid can be found in leafy green vegetables, beans, peas, and fortified cereals and bread.
Calcium. Compared to men, women are at greater risk for osteoporosis, in which bones become weak and are more likely to break. Women need to start getting more calcium at an early age to keep bones strong. Calcium-rich foods include low-fat dairy products, tofu, kale, and fortified cereals and juices. Vitamin D is also important to help the absorption of calcium. Read more about vitamin D in HPRC’s Vitamin D, the sunshine vitamin.”
All of these nutrients can be found in supplement form, but as with any dietary supplement, consult your doctor first to determine if they are necessary and safe. For more information on supplements, read HPRC’s “Women's health and dietary supplements.” Remember, most people can achieve adequate intake of these nutrients with a balanced diet. Poor nutrition puts you at risk for injuries and makes it harder for you to perform at your best.
If you’d like to know more about women’s health, visit the Military Health System's web page.