SYNTHETIC VITAMINS
Vitamins are essential micronutrients that are required by the human body for optimal health and well-being. They are found in various food sources and are necessary for a wide range of bodily functions, including growth, development, and immune system function.
While a balanced and varied diet can provide adequate levels of vitamins, many people turn to dietary supplements to ensure they are getting enough of these vital nutrients. However, not all vitamin supplements are created equal.
Synthetic vitamins, which are made in a laboratory, are becoming increasingly popular but may come with a range of potential dangers. In this article, we will explore the risks associated with synthetic vitamins and why you may want to reconsider taking them.
Table of Contents
- Supplements Make People Sick
- Are Natural & Synthetic Nutrients Different?
- Are Synthetic Vitamins Safe?
- Negative side effects of supplemental Antioxidants
- Negative Side Effects of Supplemental Vitamin A & Beta Carotene
- Negative Side Effects of Synthetic B Vitamins
- Negative Side Effects of Supplemental Calcium
- Negative Side Effects of Supplemental Vitamin E
- Negative Side Effects of Supplemental Folic Acid
Supplements Make People Sick
After conducting multiple large clinical trials on vitamin E supplements, it has been observed that they do not consistently provide any beneficial effects in preventing chronic diseases and mortality. In fact, high doses of vitamin E supplements may even increase mortality rates. As a result, researchers have concluded that:
- The general public should refrain from consuming vitamin E supplements;
- Health professionals need to educate people that vitamin E supplements cannot reliably prevent or cure any diseases, and that high doses may even pose a risk of death; and
- Manufacturers of vitamin E supplements and the nutraceutical industry must act responsibly by warning consumers of the potential risks associated with high doses of vitamin E intake.
For the same reasons, fortification of the food supply (cereals and flours) with folic acid and other nutrients should be stopped.
In 2008, two Cochrane Reviews of high esteem determined that the consumption of beta-carotene, vitamin A, and vitamin E, either alone or in combination with other antioxidant supplements, is associated with a noteworthy rise in mortality rates. [1]
There is evidence that high doses of some supplements increase cancer risk. Despite this evidence, marketing claims by the supplement industry continue to imply anticancer benefits.
Are Natural & Synthetic Nutrients Different?
Although it is commonly believed that synthetic nutrients are nearly identical to their natural counterparts found in food, there are significant differences in the manufacturing process. Unlike natural sources, synthetic nutrients are produced artificially, potentially leading to different reactions within the body. Therefore, despite their similar chemical structure, synthetic nutrients may not be processed in the same way as natural nutrients.
Moreover, the extent to which synthetic nutrients are efficiently absorbed and utilized by the body remains unclear. Certain synthetic nutrients may be more readily absorbed, but it is still unknown if they are fully utilized by the body in the same way as natural nutrients.
The reason for this is that natural foods contain not only isolated nutrients but also a complex matrix of vitamins, minerals, co-factors, and enzymes that work together to provide optimal nutrition for the body. In contrast, synthetic nutrients lack these additional compounds, which makes it unlikely that they will be utilized in the same way by the body as natural nutrients.
Are Synthetic Vitamins Safe?
For example, studies show that natural vitamin E is absorbed twice as efficiently as synthetic vitamin E.
Some observational studies have found multivitamin use to be associated with a lower risk of heart disease and cancer. [1, 2, 3, 4]
However, other studies have found no effect, [1, 2, 3, 4, 5] while others even link multivitamin use to increased cancer risk. [1, 2, 3]
A significant study was conducted to investigate the impact of high-dose multivitamins on heart health. The study, which spanned nearly 5 years, found no evidence of any positive effects of multivitamins on heart health.
In contrast, several other studies have linked multivitamin supplements to improved memory in older adults. [1, 2, 3]
Nevertheless, the Physicians’ Health Study II found that 12 years of daily multivitamin use did not affect brain function or memory for men over 65.
One review found no clear evidence that single or paired supplements benefit heart disease.
However, some previous studies suggest that B vitamins like folic acid may improve brain function, yet other strong studies report that dietary supplements, including B vitamins, do not improve brain function. [1]
Despite knowing that adequate vitamin D levels are critical for good health and disease prevention, vitamin D supplements are also under much scrutiny. [1]
Vitamin D supplements have been linked to numerous benefits related to cancer, bone health and brain function, to name a few. Yet experts agree more evidence is needed. [1]
One thing experts generally agree on is that vitamin D supplements, when combined with calcium, can improve bone health in older people.
Negative Side Effects of Supplemental Antioxidants
Several reviews have found no evidence to support antioxidant supplements, including beta-carotene, vitamins A, C, E, and selenium (alone or in combination) for reduced risk of death and cancer. [1]
In fact, beta-carotene supplements have been shown to increase the risk of cancer in smokers.
Nonetheless, antioxidant vitamins and minerals may help slow down the progression of diseases that cause blindness. [1]
Pregnant women need to be especially careful with their vitamin A intake, as excess amounts have been linked to birth defects.
Results from many clinical trials show that beta-carotene, vitamin E, and possibly high doses of vitamin A can increase the risk of premature death. [1]
Other studies have linked multivitamin use to increased cancer risk, and iron supplements can be harmful for people who don’t need them. [1, 2, 3]
In a clinical trial involving 20,536 adults with coronary disease, occlusive arterial disease, or diabetes, participants were randomly assigned to either receive daily antioxidant vitamin supplementation (vitamin E, vitamin C, and beta-carotene) or a placebo. The study found that the vitamin supplementation increased the concentration of vitamins in the participants’ blood, but did not result in a reduction in vascular disease, cancer, or death.
There is also some evidence that synthetic folic acid is more harmful than the natural folate in foods. It may build up in the body and raise the risk of cancer. [1, 2]
Negative Side Effects of Supplemental Vitamin A & Beta Carotene
Research has linked supplemental vitamin A and beta carotene to an increased risk of certain cancers.
A review of 49 studies found that supplementation with vitamin A was associated with a 16% higher risk of cancer. It also found that when taken on its own in supplemental form, beta carotene was associated with a 6% increased risk of death from all causes.
Beta carotene is a provitamin A, which means that it gets converted into vitamin A in the body. Beta carotene supplements have also been shown to significantly increase the risk of lung cancer in people who smoke.
Additionally, high vitamin A levels from taking high-dose supplements have been associated with low bone mineral density and increased fracture risk in women, especially among women with low vitamin D levels.
The following study used a sample size of 22,748 women and divided them into three groups. The first group consumed 10,000 IU of synthetic vitamin A, the second group consumed 20,000 IU of synthetic vitamin A and the third group consumed vitamin A from whole foods.
Women who:
- took 10,000 IU daily from nutritional supplements had a 240% greater incidence of having a child with birth defects, and those who
- took 20,000 IU daily had a 400% increase in incidence of having a child with birth defects.
A study involving 18,314 participants who were smokers, former smokers, or workers exposed to asbestos was conducted to evaluate the effects of beta-carotene and retinol (vitamin A) supplementation on mortality, lung cancer, and cardiovascular disease. Participants were randomly assigned to receive either the supplement or a placebo.
The results indicated that the group taking the supplement had a 17% higher incidence of deaths, a 46% higher incidence of lung cancer, and a 26% higher incidence of cardiovascular disease compared to the placebo group. The results were highly consistent with those found for beta-carotene in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study in 29,133 male smokers in Finland.
The Alpha-Tocopherol, Beta-Carotene (ATBC) Lung Cancer Prevention Study was a randomized, double-blind, placebo-controlled, 2 x 2 factorial design, primary prevention trial testing the hypothesis that alpha-tocopherol (50 mg/day) and beta-carotene (20 mg/day) supplements reduce the incidence of lung cancer and possibly other cancers.
The study lasted between 1985 and 1993 and 29,133 eligible male smokers aged 50 to 69 years at entry were randomized to receive daily active supplements or placebo capsules for 5 to 8 years. The results noted 18% more lung cancer and 8% more deaths among those who took synthetic beta-carotene.
Negative Side Effects of Synthetic B Vitamins
In a study involving 636 patients who had heart artery stents, the effects of folic acid, vitamin B6, and vitamin B12 supplementation on restenosis and the need for repeat heart surgery were investigated. Participants were randomly assigned to receive either the supplement or a placebo. The results showed that those who took the supplement with folic acid experienced greater restenosis, which led to an increased need for repeat heart surgery.
A study involving 238 participants with type-1 or -2 diabetes and a clinical diagnosis of diabetic nephropathy was conducted to evaluate the effects of folic acid, vitamin B6, and vitamin B12 supplementation on kidney function and vascular events. Participants were randomly assigned to receive either the vitamin supplement or a placebo.
The results showed that the vitamin group had a decline in kidney function and a significantly higher incidence of vascular events, with twice as many events compared to the placebo group.
Negative Side Effects of Supplemental Calcium
Many people consume supplemental calcium in hopes of supporting bone health. Even though supplemental calcium may be appropriate under certain circumstances, high-dose supplementation may lead to complications.
A review of 42 studies found that while calcium from food sources did not increase the risk of heart disease, calcium supplements might increase heart disease and heart attack risk.
Another review found that the use of calcium supplements increased the risk of heart disease and heart attacks by as much as 20% and 21%, respectively.
A recent review of 13 double-blind, randomized controlled trials found that calcium supplements were associated with a 15% increased risk of heart disease in healthy postmenopausal women.
This is because having elevated calcium levels may contribute to the calcification of arteries, a known risk factor for heart disease.
Negative Side Effects of Supplemental Vitamin E
Supplemental vitamin E may be necessary for certain groups of people, including people with medical conditions that affect fat absorption. However, high-dose supplemental vitamin E isn’t appropriate for most and has been linked to adverse health effects.
For example, supplemental vitamin E has been associated with an increased risk of cancer in certain populations.
Furthermore, high-dose supplemental vitamin E may lead to an increased risk of bleeding.
A study involving 652 non-institutionalized elderly individuals was conducted to evaluate the effects of multivitamin-minerals and vitamin E supplementation on respiratory infections. Participants were randomly assigned to receive either multivitamin-minerals, 200 mg of vitamin E, a combination of both, or a placebo. The results showed no significant difference in the frequency of respiratory infections between the groups. However, the severity of respiratory infections was found to be worse among those taking vitamin E.
A study involving 9,541 patients was conducted to investigate the effects of vitamin E supplementation on cancer and cardiovascular deaths. Participants were randomly assigned to receive either vitamin E or a placebo. The results indicated no significant difference in cancer or cardiovascular deaths between the two groups. However, patients in the vitamin E group were found to have a higher risk of heart failure.
A study involving 35,533 men was conducted to assess the effects of selenium and vitamin E supplementation on prostate cancer prevention. Participants were randomly assigned to one of four groups: selenium, vitamin E, selenium plus vitamin E, or placebo.
The results indicated that the vitamin E groups had a 13% higher incidence of prostate cancer (statistically non-significant), but none of the supplement interventions were found to prevent prostate cancer.
Negative Side Effects of Supplemental Folic Acid
Unlike the folate naturally found in food, folic acid from supplements and fortified foods has been associated with an increased risk of certain health conditions.
Due to the high absorption rate of folic acid, taking in large doses of folic acid (over 400 mcg per day) from supplements or fortified foods may lead to high levels of unmetabolized folic acid (UMFA) in the blood.
One study found week evidence linking high maternal UMFA blood levels to an increased risk of autism spectrum disorder (ASD) among their offspring.
High-dose folic acid supplements have also been linked to accelerated cognitive decline in older adults with low B12 levels which is very common in this population. They may alter the immune response in healthy adults and older women. [1, 2]
A study involving 3,749 men and women who had recently experienced an acute myocardial infarction (heart attack) was conducted to assess the effects of folic acid, vitamin B6, and vitamin B12 supplementation on homocysteine levels, as well as the risk of heart attack, stroke, and cancer. Participants were randomly assigned to one of four groups: folic acid, vitamin B12, and vitamin B6; folic acid and vitamin B12; vitamin B6; or placebo.
The results showed that the supplement with folic acid led to a 27% reduction in homocysteine levels. However, the groups that received the folic acid supplement had a 20 to 30% increased risk of heart attack, stroke, and cancer.
Additionally, a large review of meta-analyses found that having high blood folate levels was associated with an increased risk of prostate cancer.
