Ask the Doctor: Ewa Farrelly, M.D.

Q. Do dietary supplements for prevention benefit my health?

A. The majority of adults have or are currently taking one or more dietary supplements every day to improve their health. While there are some conditions that require a supplement for treatment, such as pernicious anemia, osteoporosis, pregnancy, gastric bypass, etc., there are little to no proven health benefits to incorporating vitamins, minerals or herbal products into your daily routine.

Some of the most common supplement misconceptions include:

The most common supplement I see on medication lists is calcium. Bones contain calcium, so logically doctors have recommended taking calcium to prevent osteoporosis. However, it’s not that simple. A 2017 meta-analysis (a study where data is combined from multiple similar studies) of 33 trials did not find a decrease in bone breakages in healthy people taking calcium supplements. It is also important to make sure you are not consuming calcium in excess – whether it is through your diet, supplements or a combination of two – as some studies have hinted it may increase your risk of heart disease. Some people also experience side effects such as stomach discomfort, nausea and constipation when taking calcium supplements. These risks and side effects are not found when you get calcium from your diet alone.

If you would like to keep your bones strong without taking supplements, resistance exercise is a great complement to a healthy diet. Every time you activate a muscle it pulls on the bone attached to it, stimulating that bone to get stronger. Pilates is an excellent exercise for your bones as it strengthens the core which, in turn, strengthens the hip bones and spine.

Fish Oil
Another common supplement I get asked about is fish oil. Fish oil contains omega-3 fatty acids, like DHA and EPA, which have been associated with a decreased risk of cardiovascular disease and improved brain function. However, multiple studies, including a recent 2018 meta-analysis of 10 trials, did not find a decrease in heart disease, stroke, or death in over 77,000 people taking fish oil. Fish oil supplements also have risks and side effects. Fish oil has been associated with an increased risk of bleeding, high grade prostate cancer, and can cause heartburn, nausea, and bad breath.

A natural way to ensure you consume omega-3 fatty acids is to add two servings of low-mercury fish into your diet every week. I also recommend my patients incorporate 20 minutes of moderate intensity exercise every day to help reduce your risk of heart disease.

A few years ago I didn’t even know how to spell turmeric or its active component, curcumin. Now a day doesn’t go by where I don’t see an advertisement for it. Turmeric, a spice used in curry, has been assigned a multitude of medical benefits from improving arthritis to curing cancer.

The first time I heard about it was in a lecture about preventing dementia. I will admit that right after the lecture, I went home and sprinkled turmeric in the soup I was making. When I started seeing people take high doses of it in capsules, though, I did some research, and have been unable to find a well-designed study showing benefits from taking high dose turmeric. Turmeric capsules, like all anti-inflammatory medications, can worsen stomach acid, increase bleeding risk, affect your kidneys, and decrease the absorption of vitamins and minerals from your food if taken in excess.

If you are looking to prevent dementia, the World Health Organization recommends individuals over 65 engage in at least 150 minutes of moderate intensity exercise every week.

In summary, the nutrients you are seeking when you take supplements can usually be obtained with a healthy, well-balanced diet. A healthy diet combined with exercise prevents disease better than any supplement. Please take the time to go through your medicine cabinet to see what supplements you are taking and speak with your physician to see what is right for you based on your health needs.

Ewa Farrelly, M.D., was born in Warsaw, Poland but grew up in San Diego, studied mathematics at UC Berkeley, and completed her medical degree at Keck School of Medicine at USC. She was chief resident at the Long Beach Memorial Family Medicine Residency Program and then practiced in Long Beach for a few years before joining Forman Family Medicine in Newport Beach.