1) One of the biggest differences between fat-soluble vitamins and water-soluble vitamins is that water-soluble vitamins are not stored in the body. Because the body is not able to store these vitamins, they must be constantly resupplied. As water soluble vitamins enter the body, they are put to work immediately and any excess is eliminated from the body via the urine. The vitamins that make up the water soluble category include the B vitamins, Vitamin C and Biotin. By contrast, fat-soluble vitamins, including vitamins A, D, E and K, are absorbed through the large intestines. For this absorption process to work properly, there must also be some dietary fat present. The body will find it difficult to complete the absorption process if fat is not eaten along with the fat soluble vitamins. Once fat soluble vitamins have been absorbed, they are stored in the liver where they wait until called upon to do their jobs.

2) Phytochemicals are plant chemicals that are neither vitamins nor minerals; yet, they have health-enhancing effects: phytochemicals help protect against cancer, cardiovascular disease and other diseases. Many phytochemicals are also antioxidants.
Antioxidants are chemical substances that donate an electron to the free radical and convert it to a harmless molecule. Antioxidants intercept free radicals and protect cells from the oxidative damage that leads to aging and disease. Antioxidants prevent injury to blood vessel membranes, helping to optimize blood flow to the heart and brain, defend against cancer-causing DNA damage, and help lower the risk of cardiovascular disease and dementia. Some antioxidants are made in our cells and include enzymes and the small molecules glutathione, uric acid, coenzyme Q-10 and lipoic acid. Other essential antioxidants such as vitamin C, E, and selenium must be obtained from our diet. Fruits, vegetables and grains are rich sources of antioxidant vitamins minerals and phytochemicals (botanicals).

3) Many dietary supplements are not only vitamins and minerals. They also include other less-familiar substances, such as herbals, botanicals, amino acids, enzymes, and animal extracts. Some dietary supplements are well understood and established, but others need further study. Whatever your choice, supplements should not replace the variety of foods important to a healthful diet.
Unlike drugs, dietary supplements are not pre-approved by the government for safety or effectiveness before marketing. Also, unlike drugs, supplements are not intended to treat, diagnose, prevent, or cure diseases. But some supplements can help assure that you get an adequate dietary intake of essential nutrients; others may help you reduce your risk of disease. Some factors to remember are:
1) Consider your total diet. Dietary supplements are intended to supplement the diets of some people, but not to replace the balance of the variety of foods important to a healthy diet. Make sure you are not getting too much of a nutrient. For example, if you eat a lot of red meat, you probably don't need an iron supplement. In fact, taking too much iron would be toxic.
2) Some supplements may interact with prescription and over-the-counter medicines. Always check for drug interactions.
3) Many supplements also contain additives. Fillers such as salt or sugars may be used to fill up space in a capsule. Corn starch or molasses might be binders that help keep a tablet intact. Be sure you are not allergic to any of these ingredients.
4) Women should always be aware of the supplement's effect on pregnancy. When in doubt, it is wisest not to take the supplement.

4) The government should play some role in setting nutritional guidelines and safety standards. Under the current law, manufacturers of dietary supplements are responsible for making sure their products are safe before they go to market. They are also responsible for determining that the claims on their labels are accurate and truthful. Dietary supplement products are not reviewed by the government before they are marketed, but the FDA (Food and Drug Administration) has the responsibility to take action against any unsafe dietary supplement product that reaches the market. If FDA can prove that claims on marketed dietary supplement products are false and misleading, the agency may take action also against products with such claims. In addition, the government-established Recommended Daily Allowances (RDAs) were created as a guideline to vitamin and mineral requirements. These guidelines can be helpful for people evaluating their diets and deciding whether or not to take a supplement. This is probably the right role for the government to play: some regulation but not too much control.

5) Critical thinking is the intellectual process of actively and skillfully conceptualizing, applying, analyzing, synthesizing, and/or evaluating information gathered from, or generated by, observation, experience, reflection, reasoning, or communication, as a guide to belief and action. It is typically associated with solving complex real world problems, generating multiple (or creative) solutions to a problem, drawing inferences, synthesizing and integrating information, distinguishing between fact and opinion, or estimating potential outcomes, but it can also refer to the process of evaluating the quality of one's own thinking. By contrast, non-critical thinking can take the form of habitual thinking (thinking based on past practices without considering current data); brainstorming (saying whatever comes to mind without evaluation); creative thinking (putting facts, concepts and principles together in new and original ways); prejudicial thinking (gathering evidence to support a particular position without questioning the position itself); or emotive thinking (responding to the emotion of a message rather than the content).

6) Perception can be defined as a person's mental image of the world. It is is the process of acquiring, interpreting, selecting, and organizing sensory information. Many cognitive psychologists hold that, as we move about in the world, we create a model of how the world works. On the other hand, reality is defined as "the quality or state of being actual or true."
For example, the earth was "perceived" to be flat which influenced people's understanding, beliefs, and behaviors. The "reality" turned out to be something significantly different: the earth is round! It is probably a more accurate statement is to say "perception may be reality" or "perception is perception of reality" rather than the more common "perception is reality."