Brigitte Zeitlin, M.P.H., R.D., C.D.N., founder of the New York-based BZ Nutrition, tells SELF, "Eating regularly throughout the day keeps your metabolism running at full speed, prevents dips in your energy, keeps you alert and focused, and [can help keep] your weight steady by preventing overeating at later meals." She and other experts recommend eating every three to four hours. If you don't, there are a number of unpleasant symptoms you may encounter.
A healthy vegetarian diet falls within the guidelines offered by the USDA. However, meat, fish and poultry are major sources of iron, zinc and B vitamins, so pay special attention to these nutrients. Vegans (those who eat only plant-based food) may want to consider vitamin and mineral supplements; make sure you consume sufficient quantities of protein, vitamin B12, vitamin D and calcium. You can obtain what you need from non-animal sources. For instance:
In 1994, the United States Congress passed a law defining nutritional supplements, and requiring them to be labeled as dietary supplements and identified as not intended to be a substitute for certain foods. A nutritional supplement can be defined as a product intended for consumption in tablet, capsule, powder, soft gel, gel cap, or liquid form, and containing vitamin(s), mineral(s), herb(s), other botanicals, amino acids, or any combination thereof.
A review of clinical trials registered at clinicaltrials.gov, which would include both drugs and supplements, reported that nearly half of completed trials were sponsored wholly or partially by industry.[125] This does not automatically imply bias, but there is evidence that because of selective non-reporting, results in support of a potential drug or supplement ingredient are more likely to be published than results that do not demonstrate a statistically significant benefit.[125][126] One review reported that fewer than half of the registered clinical trials resulted in publication in peer-reviewed journals.[127]
Calcium: For adult women aged 19-50, the USDA recommended daily allowance is 1,000 mg/day. For women over 50, the recommended daily allowance is 1,200 mg/day. Good sources of calcium include dairy products, leafy green vegetables, certain fish, grains, tofu, cabbage, and summer squash. Your body cannot take in more than 500 mg at any one time and there’s no benefit to exceeding the recommended daily amount.
The new guidelines encourage eating more nutrient-dense food and beverages. Many of us consume too many calories from solid fats, added sugar and refined grains. The guidelines promote a diet that emphasizes vegetables, fruits, whole grains, fat-free or low-fat dairy products, seafood, lean meat and poultry, eggs, beans and peas, and nuts and seeds.

As continual research on the properties of supplements accumulates, databases or fact sheets for various supplements are updated regularly, including the Dietary Supplement Label Database,[5] Dietary Supplement Ingredient Database,[104] and Dietary Supplement Facts Sheets of the United States.[105] In Canada where a license is issued when a supplement product has been proven by the manufacturer and government to be safe, effective and of sufficient quality for its recommended use, an eight-digit Natural Product Number is assigned and recorded in a Licensed Natural Health Products Database.[106] The European Food Safety Authority maintains a compendium of botanical ingredients used in manufacturing of dietary supplements.[107]
However, the Norwegian authorities do admit that vitamin D supplements are needed during part of the year. [1] Only part of the year? One third of Norway is within the Arctic Circle. Norway has far too little sunshine (especially during winter months) to get adequate levels of vitamin D from UVB radiation on the skin. The authorities also recommend that pregnant women take folic acid to prevent birth defects, and omega-3-fatty acids may be advisable for those who do not eat fish regularly. Norwegians have a long tradition of giving children cod liver oil, which in a daily tablespoon provides enough vitamin A and D and essential fatty acids to cover basic needs.
Oils. When cooking try to use oils from plants instead of solid fats like butter, margarine, or coconut oil. See this list of oils and fats to see how healthy each type of cooking oil and solid fat is. Most women eat too much solid fat through packaged foods like chips or salad dressing, and not enough healthy fats like olive oil or the type of fat in seafood.
Keep a record of the supplements you take in one place, just as you should be doing for all of your medicines. Note the specific product name, the dose you take, how often you take it, and the reason why you use each one. You can also bring the products you use with you when you see your health care provider.  The FDA provides a useful form, "My Medicine Record", to record the medicines and dietary supplements that you take. Share this form with your healthcare provider to discuss what's best for your overall health. 
It's trendy to think "food should be fuel" or that food is something that helps you lose (or, ahem, gain) weight. But thinking only in terms of number on the scale takes away a huge part of what eating is about: pleasure. "If you think of eating as something enjoyable and something you do without guilt or without judging yourself, and you stay active, you're less likely to overeat, have a better diet, and maintain any weight loss for the long haul," says Zied. It's true: feeling guilty about your food choices can undermine weight loss—and even pack on the pounds—while a celebratory mindset gives you more control over your diet and can thwart weight gain, found a 2014 study in the journal Appetite.
Go nuts for nuts (and seeds). From protein and healthy fats to vitamins and minerals, these superfoods pack a serious nutritional punch. Similarly, seeds like chia, flaxseed and pumpkin seeds are nutritional powerhouses too. They are an excellent source of vitamins, antioxidants, and minerals like calcium, zinc, and magnesium. You can add them to your favorite baking recipe, sprinkle them over your cereal or simply munch on them instead of a candy bar.
Sodium. Sodium is found in salt, but most of the sodium we eat does not come from salt that we add while cooking or at the table. Most of our sodium comes from breads and rolls, cold cuts, pizza, hot dogs, cheese, pasta dishes, and condiments (like ketchup and mustard). Limit your daily sodium to less than 2,300 milligrams (equal to a teaspoon), unless your doctor says something else. Check the Nutrition Facts label for sodium. Foods with 20% or more of the “Daily Value” of sodium are high in sodium.
In addition to diet, exercise and other lifestyle factors can also play an important role in bone health. Smoking and drinking too much alcohol can increase your chances of developing osteoporosis, while weight-bearing exercise (such as walking, dancing, yoga, or lifting weights) can lower your risk. Strength or resistance training—using machines, free weights, elastic bands, or your own body weight—can be especially effective in helping to prevent loss of bone mass as you age.
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