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 [38], and cooking and grinding meat reduces the energy required to digest it [40] and increases nutrient absorption [41].

When the body is stressed by disease, the gut will naturally absorb more vitamin C because the body needs more. To find the optimal dose, the intake should be increased until bowel tolerance is reached. Some people can tolerate more than 100,000 mg/d of vitamin C in divided doses during serious illness without having loose stool. Liposomal vitamin C bypasses the normal bowel tolerance because it is absorbed directly through cell membranes, so higher doses can be tolerated without diarrhea.
Men who choose to drink and can do so responsibly may benefit from one to two drinks a day, counting 5 ounces of wine, 12 ounces of beer, or 1.5 ounces of spirits as one drink. But women face an extra risk: Even low doses of alcohol can raise their risk of breast cancer. So women who choose to drink might be wise to limit themselves to half as much as men.
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.[86][87] 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.[88][89] 
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