The need for efficient detoxification and excretion is greatly increased by environmental pollution from the chemical industry, herbicides and pesticides used by industrial agriculture, antibiotic treatment of animals, transport, and plastic packaging. [29] In our polluted world, the increased toxic load may be compensated for by an increase in nutrients to promote detoxification. One can respond by taking large doses of supplements of essential nutrients, for example, antioxidants vitamin C and E, and an adequate dose of selenium, which help the body detoxify harmful chemicals. Also helpful is regularly taking sauna baths, fasting periodically, and eating an excellent diet that includes generous portions of dark green leafy vegetables and colorful vegetables and fruits. [30]
A spokesperson for optimal nutritional intake is the well-known biochemist Bruce Ames, who proposed the "triage theory of nutrients," in which enzymes responsible for cell maintenance functions evolved to have lower affinity for the essential vitamin and mineral cofactors than the enzymes responsible for short-term survival, to preserve life during times of famine. [35]

Vitamin B12.Vitamin B12 helps keep your red blood cells and nerves healthy. While older adults need just as much vitamin B12 as other adults, some have trouble absorbing the vitamin naturally found in food. If you have this problem, your doctor may recommend that you eat foods like fortified cereals that have this vitamin added, or use a B12 supplement.
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.

Compared to pharmaceutical drugs, supplements of most essential nutrients are quite harmless. However, some supplements may have poor quality, or contain toxic metals such as lead or cadmium. Therefore, it is the duty of our authorities to ensure that potentially hazardous products or supplements of poor quality are not sold, and that consumers are offered fair prices in a free market. An example where the Norwegian authorities do not follow up such basic duties is that pharmacies demand more than 1,600 Norwegian Kroner (about $190) per kg of vitamin C in powder form, which would cost less than $20 with free competition and no restrictions in permitted doses or outlets.

If you count calories, count fat calories, too. Food labels indicate how many calories come from fat, both in actual grams and in percentages. This helps you assess the percentage of fat in your diet. If the total number of fat calories is 30 percent or more of the total calories you consume in a day, you probably need to cut back. But don't be misled by terms like "lower fat." Ask yourself "lower than what?" and look at the overall percentage of fat calories in the food.
When you sit down to a meal, try to savor every bite. Especially the first few, because those are the bites you're going to enjoy most. "There is a toning down of taste buds after the first few bites," says Linda Bacon, Ph.D., professor of nutrition at City College of San Francisco. That's not the only reason to take it slow while eating. It takes your brain about 20 minutes to realize your stomach is full. If you're throwing back food like there's no tomorrow, odds are you're going to accidentally eat past the full and wind up totally stuffed.

A potato comes from the ground, an egg from a hen. But where did that Pop-tart come from? "Unprocessed, whole foods will give you the most benefits," Berman says. Processing takes out nutrients such as antioxidants and fiber. What's worse is that a lot of processed foods tend to sneak in things that aren't really necessary like extra sodium and sugar. There's nothing wrong with indulging the occasional processed food craving (sometimes a bag of potato chips is too hard to resist!). But if you're trying to shop healthier altogether, be on the lookout for products that have been minimally processed.

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]