An optimum intake of all nutrients is difficult to achieve even for those who eat almost exclusively an excellent diet of nutrient dense foods, such as meat and innards, fish, shellfish, fowl, eggs, nuts, mushrooms, and vegetables, berries and nutritious fruits. Some nutrients such as folic acid or carotenoids in vegetables are absorbed better from processed than unprocessed foods. Although vegetables are often considered to be a good source of vitamins, for example vitamin A from carrots, vitamin A is only found in animal products such as liver, egg yolk, fish cod and cod liver oil. Although eating raw vegetables is helpful for several reasons (vitamin C, fiber, microbiota), carotenoids (alpha/beta-carotene, lutein, lycopene) in vegetables are less well absorbed from raw than cooked food and better absorbed in the presence of added fat. [38,39]. Nutrients in vegetables are better absorbed when finely chewed, graded, or mashed , and cooking and grinding meat reduces the energy required to digest it  and increases nutrient absorption .
If all you have time for is a quick snack from the gas station or drugstore, know that you do have options, and if you know what you're looking for, it will be easier to find. When we asked registered dietitians to recommend snacks to buy at the drugstore, they tended to go for things like nuts and seeds that pack plenty of flavor (hi, wasabi chickpeas), plenty of protein, and not a whole lot else.
SOURCES: Institute of Medicine Food and Nutrition Board, Dietary Reference Intakes: "Calcium, Phosphorus, Magnesium, Vitamin D and Fluoride." National Academy Press, Washington, D.C., 1999. Journal of Nutrition, October 2005. Position paper of the American Dietetic Association on Food Fortification and Supplementation, Journal of the American Dietetic Association, August 2005. Michael Holick, MD, PhD, professor of medicine, physiology, and biophysics, Boston University Medical Center. Andrew Shoa, PhD, vice president for regulatory affairs, Council for Responsible Nutrition. Alice Lichtenstein, DSc, director and senior scientist, Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging, Tufts University. Dave Grotto, RD, spokesman, American Dietetic Association; author, 101 Foods That Could Save Your Life. Eduardo Baetti, MD, rheumatologist; Kaiser Permanente. Patrick Rea, editorial director, Nutrition Business Journal. Kristine Clark, PhD, RD, director of sports nutrition, Penn State University. Vasilios Frankos, PhD, Division of Dietary Supplement Programs, FDA. Sarubin, A. The Health Professionals Guide to Popular Dietary Supplements, American Dietetic Association, Chicago, IL, 2000. FDA. WebMD Weight Loss Clinic Feature: "Are You Getting Enough Vitamin D?" National Center for Complementary and Alternative Medicine: "Questions and Answers About Homeopathy."
Some supplements may have side effects, especially if taken before surgery or with other medicines. Supplements can also cause problems if you have certain health conditions. And the effects of many supplements haven’t been tested in children, pregnant women and other groups. So talk with your health care provider if you’re thinking about taking dietary supplements.
There are thousands of dietary supplements on the market, including 40+ essential nutrients alone and in various combinations, i.e. vitamins, minerals, trace elements and fatty acids. However, a number of other nutrients are "conditionally essential", meaning that the body normally can make these molecules, but some people do not make optimal amounts. Examples are L-carnitine, alpha-lipoic acid, the methyl donor betaine,  chondroitin sulfate, coenzyme Q10, choline, amino acids such as tyrosine or arginine, and "essential" sugars normally formed in the body. 
I realize that none of the above foods have 100% DV of calcium, and while we all should be getting a variety of these foods through the week to help increase the amount of calcium from whole foods, you can also boost it with a supplement- especially if you fall into any of the above categories. I’ve really been liking the New Chapter’s Every Woman’s One Daily Multivitamin which has calcium and is rich in vitamin D3. Read more on that in the next question!
"A smoothie with only fruits and fruit juice is essentially dessert!" Rebecca Lewis, in-house R.D. at HelloFresh, tell SELF. Smoothies can definitely be a healthy meal option, provided you're using vegetables in addition to those fruits, and high-protein, high-fiber ingredients like almond milk and chia seeds. Unfortunately a lot of smoothies (especially store-bought varieties) tend to pack in sugar. In fact, a small size at common smoothie stores like Jamba Juice can often contain more than 50 grams of sugar. To be sure you don't end up with a total gut bomb, consider making smoothies yourself. Or double check the ingredient list at your favorite shops and supermarkets.
Specialty products may offer particular health benefits or are targeted for specific conditions. These products may consist of whole foods or may be isolated compounds from natural or synthetic sources. Examples include antioxidants, probiotics (supplements containing friendly bacteria for the digestive tract), digestive enzymes, shark cartilage, or other animal products, or chemical extracts such as the hormone DHEA (dehydroepiandrosterone) and coenzyme Q10, an antioxidant.
Do you wonder if you need a dietary supplement? Maybe you do, but usually not. Ask yourself why you think you might want to take a dietary supplement. Are you concerned about getting enough nutrients? Is a friend, a neighbor, or someone on a commercial suggesting you take one? Some ads for dietary supplements in magazines, online, or on TV seem to promise that these supplements will make you feel better, keep you from getting sick, or even help you live longer. Often, there is little, if any, good scientific research supporting these claims. Supplements may cost a lot, could be harmful, or simply might not be helpful. Talk to your doctor or a registered dietitian for advice.
In its natural state, sugar is a relatively harmless — even necessary — carbohydrate our bodies need to function. It’s found in fruits, vegetables and dairy as the compound fructose or lactose. The problem comes when sugar is added to foods during processing for added flavor, texture or color. Eating too many of these empty calories has many health effects, the most obvious being major weight gain. Added sugar drives your insulin levels up, messes with your metabolism and causes those calories to turn right into belly fat. Sugar goes by many names. Learn more about the surprising benefits of cutting back on sugar.
For example, while increased consumption of fruits and vegetables are related to decreases in mortality, cardiovascular diseases and cancers, supplementation with key factors found in fruits and vegetable, like antioxidants, vitamins, or minerals, do not help and some have been found to be harmful in some cases. In general as of 2016, robust clinical data is lacking, that shows that any kind of dietary supplementation does more good than harm for people who are healthy and eating a reasonable diet but there is clear data showing that dietary pattern and lifestyle choices are associated with health outcomes.
Part of the reason why so many women fail to get the amount of iron they need is because one of the best sources of iron is red meat (especially liver) which also contains high levels of saturated fat. While leafy green vegetables and beans are also good sources of iron—and don’t contain high levels saturated fat—the iron from plant foods is different to the iron from animal sources, and not absorbed as well by the body. Other foods rich in iron include poultry, seafood, dried fruit such as raisins and apricots, and iron-fortified cereals, breads, and pastas.