Which supplements should people take to help promote good health, and at what doses? Vitamins? Minerals? Herbs? Nutraceuticals? Perhaps the best answer is before experimenting with exotic dietary supplement ingredients, it first makes sense to start out with the three dietary supplements that everyone should be taking. This includes a multivitamin, vitamin D and omega- fatty acids.

MULTIVITAMINS

There is a good case for the daily use of a multivitamin, as a nutrition insurance policy that helps to fill in the gaps for those nutrients people may not be getting in their diet. Furthermore, in a study1 of 90,771 men and women, the regular use of a multivitamin was found to significantly improve adequate intake of nutrients compared to non-users. Also, research2 found that multivitamin supplements are generally well tolerated, do not increase the risk of mortality, cerebrovascular disease, or heart failure, and their use likely outweighs any risk in the general population (and may be particularly beneficial for older people). So, the bottom line is that multivitamins really do work as a nutrition insurance policy.

Other multivitamin benefits
In addition to functioning as a nutrition insurance policy, the daily use of a multivitamin may offer other benefits as well.

Cardiovascular Disease
A 12-week, randomized, placebo-controlled study3 of 182 men and women (24 to 79 years) found that a multivitamin was able to lower homocysteine levels and the oxidation of LDLcholesterol—both of which are highly beneficial in reducing the risk for cardiovascular disease. Other multivitamin research4 has also demonstrated effectiveness in lowering homocysteine levels.

A 6-month, randomized, double-blind, placebo-controlled study5 of 87 men and women (30 to 70 years) found that multivitamin use was associated with lower levels of C-reactive protein, a measurement of inflammation associated with cardiovascular disease and other degenerative diseases. Other multivitamin research6 in women has shown similar results.

A Swedish, population-based, case-control study7 of 1296 men and women (45 to 70 years) who previously had a heart attack and 1685 healthy men and women as controls, found those using a multivitamin were less likely to have a heart attack. Other multivitamin research8 in Swedish women has shown similar results.

Cancer:
A large-scale, randomized, double-blind, placebo-controlled study9 was conducted with 14,641 male U.S. physicians initially 50 years or older, including 1312 men with a history of cancer, to determine the long-term effects of multivitamin supplementation on the incidence of various types of cancers. Results showed that during a median follow-up of 11.2 years, men with a history of cancer who took a daily multivitamin had a statistically significant reduction in the incidence of total cancer compared to those taking a placebo.

Stress/Energy:
A human clinical study10 with 96 healthy men (18 to 46 years) examined the effect of multivitamin supplementation in relation to plasma interleukin-6 (IL-6, a pro-inflammatory chemical produced by the body) and anger, hostility, and severity of depressive symptoms. The results showed that plasma IL-6 was associated with anger, hostility, and severity of depressive symptoms, and that multivitamin use was associated with lower plasma IL-6 levels.

A review11 of the scientific literature indicated that patients complaining of fatigue, tiredness, and low energy levels may have low levels of vitamins and minerals. Certain risk groups like the elderly and pregnant women were identified, as was the role of B-vitamins in energy metabolism. Results found that supplementation with nutrients including B-vitamins (e.g., a multivitamin) can alleviate deficiencies, but supplements must be taken for an adequate period of time.

A meta-analysis12 of eight randomized and placebo-controlled studies evaluated the influence of diet supplementation on stress and mood. Results showed that supplementation reduced the levels of perceived stress, mild psychiatric symptoms, anxiety, fatigue, and confusion. Supplements containing high doses of B-vitamins (e.g., multivitamins) may be more effective in improving mood states.

Aging:
At the ends of our chromosomes are stretches of DNA called telomeres. These telomeres protect our genetic data, making it possible for cells to divide. Each time a cell divides, telomeres get shorter. When they get too short, the cell can no longer divide and becomes inactive or “senescent” or dies. This process is associated with aging. In a cross-sectional analysis of data from 586 women (35 to 74 years), multivitamin use was assessed, and relative telomere length was measured. The results were that multivitamin use was significantly associated with longer telomeres. Compared with nonusers, the relative telomere length was on average 5.1 percent longer among daily multivitamin users. It is possible, therefore, that multivitamins may help us live longer.

VITAMIN D

Vitamin D is the “sunshine vitamin,” so coined because exposure to the sun’s ultraviolet light will convert a form of cholesterol under the skin into vitamin D. This nutrient is best known for its role in helping to facilitate the absorption of calcium and phosphorus (as well as magnesium), and so helping to promote bone health.13 Over the past decade, however, research on vitamin D has identified numerous other roles it plays in human health and wellness, which includes:

  • Inhibiting the uncontrolled proliferation of cells (as in the case of cancer) and stimulating the differentiation of cells (specialization of cells for specific functions).14
  • Helping prevent cancers of the prostate and colon.15,16
  • Functioning as a potent immune system modulator.17,18
  • Helping prevent autoimmune reactions.19,20,21
  • Helping improve insulin secretion.22,23,24
  • Decreasing the risk of high blood pressure via the reninangiotensin system’s regulation of blood pressure.25
  • Reducing osteoporotic fractures.26,27,28
  • Reducing the incidence of falls in older adults.29,30
  • Reducing the risk of developing premenstrual syndrome (PMS).31
  • Reducing the prevalence of depression, especially in the elderly.32
  • Reducing the prevalence of urinary infections and lower urinary tract symptoms (e.g., benign prostatic hyperplasia or BPH).33

Vitamin D deficiency and insufficiency
Outright vitamin D deficiency is present in 41.6 percent of the U.S. population,34 while vitamin D insufficiency (i.e., lacking sufficient vitamin D) is present in 77 percent of the world’s population.35 If you are deficient in vitamin D you will not be able to absorb enough calcium to satisfy your body’s calcium needs.36 It has long been known that severe vitamin D deficiency has serious consequences for bone health, but other research indicates that lesser degrees of vitamin D deficiency are common and increase the risk of osteoporosis and other health problems.37,38

Vitamin D sufficiency is measured by serum 25-hydroxyvitamin D levels in the body.39 Laboratory reference ranges for serum 25-hydroxyvitamin D levels are based upon average values from healthy populations. However, recent research examining the prevention of secondary hyperparathyroidism and bone loss suggest that the range for healthy 25-hydroxyvitamin D levels should be considerably higher. Based upon the most current research, here are the ranges for serum 25-hydroxyvitamin D values:

  • Less than 20–25 nmol/L: Indicates severe deficiency associated with rickets and osteomalacia.40,41
  • 50–80 nmol/L: Previously suggested as normal range.42
  • 75–125 nmol/L: More recent research suggests that parathyroid hormone43,44 and calcium absorption45 are optimized at this level; this is a healthy range.46

Based upon the 75–125 nmol/L range, it is estimated that one billion people in the world are currently vitamin D deficient.47 Furthermore, research indicates that supplementation with at least 800–1,000 IU daily are required to achieve serum 25-hydroxyvitamin D levels of at least 80 nmol/L.48,49 Furthermore, there are many groups of individuals who currently are at risk for vitamin D deficiency. These include:

  • Exclusively breast-fed infants: Especially if they do not receive vitamin D supplementation and if they have dark skin and/or receive little sun exposure.50
  • Dark skin: People with dark-colored skin synthesize less vitamin D from sunlight than those with light-colored skin.51 In a U.S. study, 42 percent of African American women were vitamin D deficient compared to four percent of white women.52
  • The Elderly: When exposed to sunlight have reduced capacity to synthesize vitamin D.53
  • Those using sunscreen: Applying sunscreen with an SPF factor of eight reduces production of vitamin D by 95 percent.54
  • Those with fat malabsorption syndromes: The absorption of dietary vitamin D is reduced in Cystic fibrosis and cholestatic liver disease.55
  • Those with inflammatory bowel disease: An increased risk of vitamin D deficiency occurs in those with inflammatory bowel disease like Crohn’s disease.56
  • Obese individuals: Obesity increases the risk of vitamin D deficiency.57

Vitamin D2 and D3
There are two forms of vitamin D available as a dietary supplement: cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). Cholecalciferol is the form made in the human body, and it is more active than ergocalciferol. In fact, Vitamin D2 potency is less than one third that of vitamin D3.58

Commercially, ergocalciferol is derived from yeast, and so is considered vegetarian, while cholecalciferol is commonly derived from lanolin (from sheep) or fish oil—although a vegetarian D3 derived from lichen is available.

Ideal dosing for vitamin D
The Linus Pauling Institute recommends that generally healthy adults take 2,000 IU of supplemental vitamin D daily.59 The Vitamin D Council states that if well adults and adolescents regularly avoid sunlight exposure, then it is necessary to supplement with at least 5,000 IU of vitamin D daily.60 The Council for Responsible Nutrition recommends 2,000 IU daily for adults.61 Taking a conservative position, at least 2,000 IU of vitamin makes sense for adults.

OMEGA-3 FATTY ACIDS
Chemically, a fatty acid is an organic acid that has an acid group at one end of its molecule, and a methyl group at the other end.62 Fatty acids are typically categorized in the omega groups 3, 6 and 9 according to the location of their first double bond (there’s also an omega 7 group, but these are less important to human health).63 The body uses fatty acids for the formation of healthy cell membranes, the proper development and functioning of the brain and nervous system, and for the production of hormone-like substances called eicosanoids (thromboxanes, leukotrienes, and prostaglandins). These chemicals regulate numerous body functions including blood pressure, blood viscosity, vasoconstriction, immune and inflammatory responses.64

Deficiency of omega-3 fatty acids
While omega-3, 6 and 9 fatty acids are all important for different reasons, it is the omega-3 fatty acids (O3FA) that are currently particularly critical—and specifically the O3FA known as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The reason for this current importance is that Western diets are deficient in O3FA, and have excessive amounts of omega-6 fatty acids. While human beings evolved on a diet with approximately a 1:1 ratio of omega-6 to omega-3 fatty acids (EFA), the current Western diet provides about a 16:1 ratio.65 As a matter of fact, a recent Harvard School of Public Health study indicates that Omega-3 deficiency causes 96,000 U.S. deaths per year.66 Other research has clearly shown that excessive amounts of omega-6 fatty acids and a very high omega-6 to omega-3 ratio, as is found in today’s Western diets, promote many diseases, including cardiovascular disease, cancer, and inflammatory and autoimmune diseases, whereas increased levels of omega-3 (a low omega-6 to omega-3 ratio) exert protective effects.67

Benefits of omega-3 fatty acids

O3FA offer a broad range of benefits in human health. These benefits are listed below categorically:

Cardiovascular Health
In several studies O3FA have been shown to help lower triglyceride levels.68 In fact, the FDA has even approved an O3FA product for this purpose.69 Individually, EPA and DHA also have triglyceride-lowering properties. Consuming 1 gram/day of fish oils from fish (about 3 ounces of fatty fish such as salmon) or fish oil supplements has a cardioprotective effect.70

Evidence suggests increased consumption of O3FA from fish or fish-oil supplements, but not of alpha-linolenic acid, reduces the rates of all-cause mortality, cardiac and sudden death, and possibly stroke.71 Higher consumption of fish and O3FA has been associated with a lower risk of coronary heart disease.72,73 Clinical research shows that DHA supplementation helps increase HDL cholesterol levels (the “good cholesterol”).74,75 Supplementation with fish oil produces modest, but significant reductions in systolic and diastolic blood pressure in patients with mild hypertension.76,77,78

Inflammation
O3FA have been shown to help relieve inflammation caused by a variety of factors.79,80

Arthritis

Research81 has demonstrated that fish oil supplementation is effective in the treatment of rheumatoid arthritis.

Menopause
Clinical research shows that taking supplements with 500 mg EPA, three times daily, modestly but significantly reduces the frequency of hot flashes compared to placebo in menopausal women.82

ADHD
Research has shown children with attention deficit/hyperactive disorder (ADHD) may have low plasma levels of EPA and DHA.83,84 Clinical research suggests that supplementation with DHA might improve aggression and social relationships in ADHD children.85

Macular degeneration
Increased dietary consumption of DHA is associated with reducing the risk of macular degeneration.86

Alzheimer’s Disease
Participants who consumed fish once per week or more had 60 percent less risk of Alzheimer’s disease compared with those who rarely or never ate fish, and this was attributed to the DHA content of the fish.87

The sources of omega-3 fatty acids

To begin with, the overwhelming majority of research on the health benefits of supplementation with O3FA has been conducted using fish oil products. Consequently, a strong argument can be made that fish oil supplements are the preferred source of O3FA. Amongst these, the primary fish used commercially as the source from which O3FA are derived include mackerel, herring, tuna, halibut, salmon and cod liver.88 Although some fish are touted as superior over others as sources for supplemental fish oil, it is the opinion of this author that they all provide acceptable sources of omega-3s. Still, there are other sources of O3FA besides fish oil. This includes squid, krill, flax seed oil and algae oil.

Squid
Squid-derived O3FA are derived from by-products of squid that are usually discarded when squid are commercially fished, and provides a much higher concentration of DHA (up to 50 percent) than do fish oil. However, there is a lack of human clinical data on squid-source O3FA, although they likely will have similar effects as fish oil.

Krill
Krill oil derived from the shrimp-like crustacean know as krill contain significant amounts of the EPA and DHA omega-3 fatty acids, as well as phospholipids (e.g., phosphatidylcholine),89 vitamin A, vitamin E and astaxanthin, a powerful carotenoid antioxidant.90,91 Human clinical research92 has shown that krill oil has greater absorption than fish oil—although krill provides significantly less EPA/DHA per gram than fish oil.

Flaxseed
Flaxseed oil contains about 52–55 percent omega-3s, but as alpha-linolenic acid (ALA), not EPA/DHA.93 This is significant since ALA has to be converted to EPA and DHA before it will provide the much-touted health benefits attributed to O3FA. This is problematic since studies indicate that in men approximately eight percent of ALA is converted to EPA and 0–4 percent is converted to DHA.94 In women, approximately 21 percent of dietary ALA is converted to EPA and nine percent is converted to DHA.95 This is not to say that flaxseed oil has no value. It does, but just not as significant a value as fish oil.

Algae oil
Certain algae extracts provide a vegetarian source of O3FA—but in this case the O3FA are EPA and DHA, not ALA. Consequently, for vegetarians, algae oil is a viable substitute for fish oil. That being said, human clinical research on algae oil sources of O3FA is limited, and the cost is far more than fish oil.

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