Do We Really Need Vitamin D Supplements?
First let me say that I’m not a doctor, nor am I giving you medical advice. The only reason I’m writing this is because I just completed my annual physical and during the last appointment that I had with my primary doctor, he asked me if I was still taking Vitamin D supplements. I told him I was but I had no idea why, I was just taking them because he suggested that I did. He thought that was pretty funny but he mentioned some of the reasons: It helps my immune system, bone health (especially as I got older), it helps with communication from my nerves to my brain, cell growth and several other things.
I was curious and started to do a little research when I got home. I went to the Mayo Clinic website (always my go-to website) https://www.mayoclinic.org/drugs-supplements-vitamin-d/art-20363792
as well as Stanford University’s Lifestyle Medicine website https://longevity.stanford.edu/lifestyle/2024/03/11/vitamin-d-benefits-sources-deficiency/ . Both websites seem to agree that in a perfect world you can get enough vitamin D with a proper diet and both websites agree that it’s usually not a perfect world and both mention supplements.
How does Vitamin D help your body?
- Bone health: Vitamin D helps your body absorb calcium, which is a key component of strong bones. It also helps prevent osteoporosis, a disease that weakens bones and makes them more likely to break.
- Muscle and nerve function: Vitamin D is necessary for muscles to move and nerves to promote communication between body and brain.
- Immune system: Vitamin D helps your immune system fight off viruses and bacteria.
- Inflammation: Vitamin D can help reduce inflammation.
- Cell growth: Vitamin D helps regulate cell growth.
- Glucose metabolism: Vitamin D helps regulate glucose metabolism.
- It has also been hypothesized that vitamin D may reduce the risk of falls in older adults by enhancing muscle strength and coordination, thus improving balance and postural sway. An analysis of multiple studies indicates that daily vitamin D supplementation may decrease the risk of falls in older adults with low vitamin D levels. However, this protective effect was not observed in individuals with sufficient vitamin D levels, a conclusion supported by the VITAL trial https://www.vitalstudy.org/findings.html daily.
You can get vitamin D from your diet, supplements, or by exposing your skin to sunlight. However, too much sun exposure can lead to skin cancer and aging.
A lack of vitamin D can lead to bone deformities in children and bone pain in adults. Some studies suggest that vitamin D may help protect against cancer, heart disease, and infections, but they are still conducting research on that.
Vitamin D can increase calcium levels, so it should be used with caution in people with certain conditions, such as kidney disease, tuberculosis, or lymphoma.
Sunlight
The primary source of vitamin D is the production that occurs in our skin from cholesterol precursors when exposed to the sun’s ultraviolet-B (UVB) rays, earning its nickname “the sunshine vitamin.” Vitamin D does play an important role in keeping our bodies healthy so daily exposure to some sunlight is recommended but proceed with caution if you are prone to skin problems.
Some plants and animals also possess the ability to synthesize vitamin D, contributing to the vitamin’s content in various foods and supplements. In plants, vitamin D is in the form D2 (ergocalciferol), while in animals, including humans, it is in the form D3 (cholecalciferol). Both forms are absorbable by humans; however, there is evidence suggesting that D3 has a more substantial and prolonged impact. Again, check with your doctor first.
Food
High amounts of vitamin D3 are found in oily fishes such as salmon, mackerel, and sardines, whereas small amounts are found in eggs, red meat, and liver.
Vitamin D2 is found in specific mushrooms, but its concentrations vary significantly based on exposure to light. Mushrooms, much like our skin, require sunlight for vitamin D production. “Since commercially available mushrooms are typically grown in dark conditions, they contain minimal amounts of vitamin D and organic mushrooms will contain almost none. Exposure to UV light through irradiation, which is not allowed in organic food production, will substantially increase conventional mushroom vitamin D content,” said Rachele Pojednic, PhD, Stanford University nutrition and exercise scientist.
Due to the limited natural food sources of vitamin D, many products, including breakfast cereals, dairy items, and plant-based milks, are fortified with vitamin D2 and D3. For a comprehensive list of vitamin D content in specific foods, refer to the U.S. Department of Agriculture (USDA) list categorized by nutrient content and food name.
Supplements
Vitamin D2 and D3 can be found in supplement form. Due to the potentially higher bioavailability, D3 supplements are typically recommended over D2.
Few foods are naturally rich in vitamin D3. The best sources are the flesh of fatty fish and fish liver oils. Smaller amounts are found in egg yolks, cheese, and beef liver. Many foods and supplements are fortified with vitamin D like dairy products and cereals. Cod liver oil Salmon Swordfish Tuna fish Orange juice fortified with vitamin D Dairy and plant milks fortified with vitamin D Sardines Beef liver Egg yolk Fortified cereals Source: https://nutritionsource.hsph.harvard.edu/vitamin-d/
“Ever since vitamin D deficiency was found to be the root cause of rickets, we have long recognized its role in bone health. Now research is looking at this vitamin as a panacea for numerous ailments, from the common cold, to even cancer,” states Robert Oh, MD, MPH, Chief Wellness Officer of the VA Palo Alto Healthcare System.
How Much Vitamin D Do I Need?
Optimal levels of vitamin D vary among individuals based on factors such as age, race, metabolic differences, and physiological condition. Adding complexity to this understanding, Dr. Pojednic emphasizes that most vitamin D recommendations are based solely on bone health, and levels required to support other tissues may vary. As such, there is no universally accepted optimal vitamin D level for overall health.
Dr. Oh recommends optimizing natural sources of vitamin D first, such as averaging about 30 minutes in the sun most days, and including a few servings of vitamin D-rich foods in their diet.
Dr. Pojednic adds that achieving these levels does not need to be daily practice. “Since vitamin D is a fat-soluble vitamin, our fat cells can store excess for weeks. Therefore, it is more important to consider average sunlight exposure and vitamin D consumption rather than focusing on daily intakes,” she says.
Because vitamin D is stored in fat cells, excessive doses can build up to toxic levels, therefore taking high doses of vitamin D (i.e. more than 4,000 IU per day) can be dangerous and should be avoided. Symptoms of vitamin D toxicity include weight loss, irregular heartbeat, hardening of blood vessels and tissue due to increased blood levels of calcium, potentially leading to damage of the heart and kidneys.
The bottom line, check with your doctor to determine what’s the correct amount of Vitamin D is required for your health. I hope this blog helps!
Sal Coppolino
Instructor and VP
International CPR Institute, Inc.
