You should eat a healthful, well-balanced diet during pregnancy. However, you should avoid certain foods, including raw or undercooked fish, poultry and meat; raw or partially cooked eggs or foods containing raw eggs; unpasteurized juices; raw sprouts; unpasteurized milk products; and some soft cheeses (cream cheese is OK). Avoid deli meats and frankfurters unless they have been reheated to steaming hot before eating. To prevent food-borne illnesses, take the following precautions:
^ Jump up to: a b Committee on the Framework for Evaluating the Safety of Dietary Supplements, Food and Nutrition Board, Board on Life Sciences, Institute of Medicine and National Research Council of the National Academies (2004). Dietary supplements a framework for evaluating safety. Washington, D.C.: National Academies Press. p. ES-1-ES-3. ISBN 978-0-309-09206-7.
Other nutritional supplements include nutrient-dense food products. Examples of these are brewer's yeast, spirulina (sea algea), bee pollen and royal jelly, fish oil and essential fatty acid supplements, colostrum (a specialty dairy product), psyllium seed husks (a source of fiber), wheat germ, wheatgrass, and medicinal mushrooms such as the shiitake and reishi varieties.
To assure supplements have sufficient quality, standardization, and safety for public consumption, research efforts have focused on development of reference materials for supplement manufacturing and monitoring. High-dose products have received research attention, especially for emergency situations such as vitamin A deficiency in malnutrition of children, and for women taking folate supplements to reduce the risk of breast cancer.
(OMNS Sept 12 2018) One of the most vitamin-restrictive countries in the world is Norway. There, authorities limit potencies to only slightly higher than RDA (Recommended Dietary Allowance) levels for dietary supplements sold outside of pharmacies. The traditional reasoning is that most people receive the nutrients they need from a "balanced diet."  The authorities are also obsessively concerned that some vitamins and minerals are harmful in high doses. And, since an intake of water-soluble vitamins in excess of needs is excreted in the urine, Norwegian "experts" advise that taking supplements is a waste of money. Accordingly, the argument goes, the public should be protected not only from possible harm, but also from wasting money on unnecessary nutrients. The official policies on nutritional supplements vary within OECD (Organization for Economic Cooperation and Development) countries. Some are more liberal, while others are even more restrictive.
Whether you're visiting the drug store, grocery or natural food shop you'll likely find an aisle where there are jars and bottles of things for you to put in your body that are neither foods nor medicines. Ranging from vitamins and minerals to fiber and herbal remedies, these supplements are not regulated in the same way as either food or medicine. Some of them are backed by solid research, others are folk remedies or proprietary cures. If your diet does not include enough of certain vitamins or minerals, a supplement may be a good idea. Natural treatment for conditions like constipation may be effective. But because these substances are unregulated, it is always a good idea to educate yourself about the products and to use common sense when taking them. This is even more true if you are pregnant or taking a medicine that may be affected by supplements.
Most Americans get far more protein than they really need. In theory, that may not be wise. Like carbohydrates, protein provides 4 calories per gram, and excess calories from any source will be stored as body fat. Excess dietary protein increases calcium loss in the urine, perhaps raising the risk for osteoporosis ("thin bones," more a worry for women) and kidney stones (a particular worry for men).
The soil in areas with relatively low rainfall may in some cases contain an extremely high concentration of minerals, which is reflected in the plants growing there. This was well documented 70 years ago in the book Tomorrow's Food.  The Dentist George W. Heard found that the soil in Hereford, Texas, was exceptionally rich in minerals. Hereford became known as the "town without a toothache" after a newspaper article from January 29, 1942, reported that Hereford had the lowest incidence of tooth decay of any city in the United States.  Heard found that people in Hereford had exceptionally few dental cavities and also that the soil locally was especially rich in minerals. He emphasized that the population in the county ate unprocessed food and was drinking raw milk. 
^ MacLean CH, Newberry SJ, Mojica WA, Khanna P, Issa AM, Suttorp MJ, Lim YW, Traina SB, Hilton L, Garland R, Morton SC (2006-01-25). "Effects of omega−3 fatty acids on cancer risk: a systematic review". JAMA: The Journal of the American Medical Association. 295 (4): 403–415. doi:10.1001/jama.295.4.403. hdl:10919/79706. PMID 16434631. Retrieved 2006-07-07.
Parents are advised to become familiar with the literature on essential nutrients, for instance by consulting the Orthomolecular News Service. Children should be given supplements in appropriate doses and in a suitable form. Pills should not be given before children can control the swallowing reflex. Multivitamin powder can be given dissolved in water or juice. Parents should not dose vitamin C so high that a child comes to school or kindergarten with loose bowels or diarrhea. In high doses, niacin may cause unpleasant side effects such as flushing and itching lasting up to several hours.  Although this is not dangerous, it may cause a child to feel unwell and anxious. Starting niacin supplementation with a low dose and gradually increasing it will allow the body to adapt and avoid the niacin flush. A multivitamin supplement containing moderate amounts of niacin is often adequate until a child is 8-10 years old. For younger children, the dosage should start with only a few tens of milligrams, and not increased to more than 50-100 mg/day. Adults may gradually get used to taking 1,000-1,500 mg/d divided into 3 doses per day.
Women need more of this mineral because they lose an average of 15 to 20 milligrams of iron each month during menstruation. Without enough iron, iron deficiency anemia can develop and cause symptoms that include fatigue and headaches. After menopause, body iron generally increases. Therefore, iron deficiency in women older than 50 years of age may indicate blood loss from another source and should be checked by a physician.
Fresh, Frozen, or Canned Vegetables ― try something new. You may find that you love grilled vegetables or steamed vegetables with an herb you haven’t tried like rosemary. You can sauté (panfry) vegetables in a non-stick pan with a small amount of cooking spray. Or try frozen or canned vegetables for a quick side dish — just microwave and serve. When trying canned vegetables, look for vegetables without added salt, butter, or cream sauces. Commit to going to the produce department and trying a new vegetable each week.
Say no to sugary drinks. The average American drinks around 45 gallons of soda each year, according to the Beverage Marketing Corporation. Other than the obvious risk of Type 2 diabetes and obesity, consuming sugary beverages can also cause liver damage, premature aging and anxiety. So, instead of sipping packaged juice or soda, go for unsweetened beverages or infused water.
We've heard a lot of encouraging news about supplements. A series of studies hailed vitamin D as a possible defense against a long list of diseases, including cancer, diabetes, depression, and even the common cold. Omega-3 fatty acids have been touted for warding off strokes and other cardiovascular events. And antioxidants such as vitamins C and E and beta carotene were seen as promising silver bullets against heart disease, cancer, and even Alzheimer's disease.
Use whole grain flour in baking recipes. For some guilt-free indulgence, use whole grain flour in your baking recipes. Whole grain flour includes the bran and the germ which make it more nutritious than its refined counterpart. Start off by subbing half of the flour in the recipe with spelt flour (or any other whole grain flour of your choice) and see how it works. Here are some handy tips for baking with whole grain flours.
Among general reasons for the possible harmful effects of dietary supplements are: a) absorption in a short time, b) manufacturing quality and contamination, and c) enhancing both positive and negative effects at the same time. The incidence of liver injury from herbal and dietary supplements is about 16–20% of all supplement products causing injury, with the occurrence growing globally over the early 21st century. The most common liver injuries from weight loss and bodybuilding supplements involve hepatocellular damage with resulting jaundice, and the most common supplement ingredients attributed to these injuries are green tea catechins, anabolic steroids, and the herbal extract, aegeline. Weight loss supplements have also had adverse psychiatric effects.
Eating a healthy diet doesn’t have to be overly complicated. While some specific foods or nutrients have been shown to have a beneficial effect on mood, it’s your overall dietary pattern that is most important. The cornerstone of a healthy diet pattern should be to replace processed food with real food whenever possible. Eating food that is as close as possible to the way nature made it can make a huge difference to the way you think, look, and feel.