Are Dietary Supplements Always Safe?

SadaNews - The dietary supplement market is witnessing unprecedented expansion, with over 100,000 products ranging from capsules and tablets to powders and gummy candies, all marketed as ways to improve or maintain health.

However, this widespread presence is met with a common misunderstanding that these products are completely safe, a belief that experts warn can be dangerous, confirming that excessive intake of certain supplements can lead to serious health problems, according to a report published by the British "Telegraph".

Dr. Peter Cohen, an internist and associate professor at Harvard Medical School, says that excessive amounts of nutrients can cause health issues; therefore, it is essential to know if the correct dosage is being used from high-quality products.

Here’s what experts say about how to navigate the world of dietary supplements and what might happen if you consume excessive amounts of some common types.

Careful Selection of Supplements and Dosages

Ideally, we should obtain the nutrients we need from the food we eat. Dr. Denise Milstein, director of integrative medicine at Mayo Clinic Arizona, says, "But this is not always possible for various reasons, including difficulty accessing nutritious foods or the effects of certain medications."

What Happens If You Take Excessive Amounts?

Multivitamins:

Multivitamin supplements contain at least three vitamins and one mineral.

There are no regulations governing the nutrients that should be included in these supplements or their quantities. According to the National Institutes of Health (NIH), some of these supplements contain vitamins and minerals in amounts that exceed the upper limit allowed. Accordingly, there is a risk of getting excessive amounts of nutrients, especially if you are taking a multivitamin along with other supplements.

The potential harm depends on the type of excess nutrient. Milstein says, "Multivitamins can be complex because you have to look at each component individually, and there are many of them."

Vitamin D:

Milstein explained that "Vitamin D can become highly toxic when taken in excessive amounts." High levels are associated with harms such as nausea, vomiting, and increased urination. Extremely high levels may be linked to kidney failure, heart rhythm disorders, and death. The National Institutes of Health indicate that elevated levels are "almost always" the result of excessive supplementation.

Individual needs vary, according to Milstein. The recommended daily intake for adults aged 19 to 70 is about 15 micrograms or 600 international units. The upper limit allowed for the same age group is 100 micrograms or 4000 international units.

Omega-3 Fatty Acids:

Omega-3 fatty acids are found in certain foods, like fatty fish and chia seeds. Supplements like fish oil or cod liver oil contain two types of Omega-3: docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA).

Experts have not specified recommended amounts for these types, but the U.S. Food and Drug Administration recommends that their total not exceed 5 grams per day from dietary supplements. Mayo Clinic notes that high doses may increase the risk of bleeding and stroke.

Milstein explains that low-quality Omega-3 products carry greater risks for side effects, ranging from heartburn to nausea.

Calcium:

General guidelines recommend that adults consume 1000 to 1200 mg of calcium daily, divided into doses not exceeding about 500 mg at a time, according to Milstein. The upper limit varies by age and health conditions. Calcium can negatively interact with other supplements and medications.

Excessive calcium supplementation may lead to kidney stones. Despite conflicting research results and the need for further studies, some research indicates that calcium supplements may increase the risk of heart disease, particularly among postmenopausal women.

Vitamin C:

Vitamin C is among the most commonly used supplements, as many take it to avoid illness, according to Blake. Although it may slightly shorten the duration of colds, research indicates it does not prevent them.

Blake points out that excess vitamin C is expelled from the body through urine; however, chronic overconsumption may lead to gastrointestinal issues like nausea and diarrhea, and doses exceeding 2000 mg daily may cause stomach pain, diarrhea, and kidney stones.

Milstein recommends taking about 500 to 1000 mg daily. She says, "The problem with consuming large amounts is that it doesn't benefit you, so why stress your kidneys this way?"

Vitamin B12:

The National Institutes of Health recommend a daily intake of 2.4 micrograms of vitamin B12 for most adults, though dosages may vary by individual condition. This vitamin is available in various types of supplements, many of which contain very high doses.

Magnesium:

Magnesium supplements are available in multiple forms, such as magnesium oxide, magnesium citrate, and magnesium chloride, each having different effects. For instance, magnesium citrate is used as a laxative; thus, individuals with sensitive stomachs may want to avoid it.

In general, the recommended daily amount for adults is about 300 to 400 mg, depending on age and sex. The specific upper limit for magnesium from supplements and medications is 350 mg.

There is no risk associated with consuming excess magnesium from food, but high doses from supplements can cause nausea, abdominal cramps, and diarrhea. Extremely high doses can be fatal.

Probiotics:

There is no official recommendation for the use of probiotics in healthy individuals in general. Blake advises consulting a registered dietitian to determine the appropriate strain and dosage. Possible side effects include eczema and inflammatory bowel diseases.

If the body tolerates probiotics, excessive amounts may not be toxic but could have other subsequent effects.

Creatine:

Creatine supplements may cause some bloating and digestive disorders, in addition to nausea, according to Milstein. She recommends adhering to a dosage of 4 to 5 grams daily.

Research indicates that higher doses do not provide any additional benefits. Given mixed evidence regarding its potential adverse impact on the kidneys, individuals with kidney disease are advised to consult with a healthcare provider before using it.

Collagen Peptides:

Collagen peptides are smaller parts of collagen and can come in powder or tablet form. They may help support joint and skin health, but Carnivali emphasizes that more research is needed to support these claims.

While there is no standard dose, some studies suggest that taking 2.5 to 15 grams daily is considered safe, although research not funded by supplement companies remains limited.

Milstein's primary warning is not to use collagen peptides as a substitute for complete protein powder; they lack the essential amino acids needed for overall health.