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Supplements of vitamin D and fish oil lower your risk of rheumatoid arthritis, psoriasis, and other autoimmune diseases

Supplements of vitamin D and fish oil lower your risk of rheumatoid arthritis, psoriasis, and other autoimmune diseasesAutoimmune diseases occur in the wake of chronic inflammation and are the result of the immune defense erroneously attacking the body’s own tissues. Rheumatoid arthritis, psoriasis, sclerosis, and Hashimoto’s disease (that causes hypothyroidism) are all examples of autoimmune diseases that primarily affect women and older people. The diet plays a significant role and according to a study published in The British Medical Journal, supplements of vitamin D and fish oil taken for extended periods can lower the rate of autoimmune diseases. This is useful knowledge because these diseases are on the rise and the medicine that is used to treat them often comes with serious side effects.

It’s vital for the body to be able to fight infections. Under normal conditions, the white blood cells of the immune system launch a pro-inflammatory phase to kill the pathogens. Once the threat is over, an anti-inflammatory phase is initiated. In the case of autoimmune diseases, the immune system, by mistake, attacks the body’s own tissue with a chronic inflammatory response. The risk of acquiring an autoimmune disease increases with age and women are more likely to get one. Some of the most common autoimmune diseases are:

  • Rheumatoid arhtritis
  • Hashimoto’s thyroiditis that causes the metabolic rate to slow down
  • Graves’ disease that speeds up the metabolism
  • Psoriasis (a skin disorder)
  • Muscular rheumatism or polymyalgia reumatica (PMR)
  • Sclerosis
  • Crohn’s disease and ulcerous colitis, both of which are chronic gastrointestinal diseases
  • Type 1 diabetes

Supplements of vitamin D and omega-3 work best after two years

It is commonly known that vitamin D and omega-3 fatty acids have a positive influence on chronic inflammation through their ability to control different parts of the immune system, Still, there are no large, randomized studies that have tested if supplements of vitamin D and omega-3 fatty acids can reduce the risk of getting an autoimmune disease. Not until now, that is.
For the new study the scientists gathered data from a larger study called VITAL (Vitamin D and Omega-3 Trial), where a group of researchers from Brigham and Women’s Hospital in Boston, USA, studied nearly 26,000 adult Americans with an average age of 67 years. The greater purpose of the VITAL study was to investigate if supplements of vitamin D and fish oil could lower healthy people’s risk of developing cancer, cardiovascular disease, stroke, and other ailments. At baseline, the volunteers were asked to provide information about age, ethnicity, place of residence, income level, education, weight, medical history, diet habits, and any use of supplements. Blood samples were taken to determine levels of vitamin D and omega-3 fatty acids.

After that, the participants were divided in the following groups:

  • Vitamin D supplementation (50 micrograms/day) or placebo
  • Omega-3 supplementation (1 gram daily) or placebo

Over the following 5.3-year period, the participants were asked to report if they were diagnosed with rheumatoid arthritis, muscular rheumatism, thyroid disorders, psoriasis, or other autoimmune diseases. Any reported cases of autoimmune diseases were controlled via medical journals. If the documentation was insufficient, the autoimmune diseases were classified as being probable. In the course of the study, 123 participants in the vitamin D group got an autoimmune disease compared with 155 participants in the corresponding placebo group. In other words, taking vitamin D reduced the risk of an autoimmune disease by 22 percent.
In the omega-3 group, 130 participants were diagnosed with an autoimmune disease, compared with 145 in the corresponding placebo group. The 15 percent risk reduction was not considered statistically significant. Nonetheless, the rate of autoimmune diseases was lowered by 18 percent when those with probable autoimmune diseases were included. Also, there was a significant long-term reduction of autoimmune disease in the omega-3 group, suggesting that it may be a good idea to continue taking fish oil for a long period of time.
Similar results were seen when looking at the last three years of the study. During this period, both the vitamin D supplements and fish oil supplements lowered the number of autoimmune diseases by around 30 percent compared with placebo.
This study, the scientists point out, is the first to show that seniors who take supplements of vitamin D and omega-3 fatty acids can lower their risk of autoimmune diseases, and the effect increases after two years of taking the supplements.
A limiting factor is the fact that the participants were given doses of vitamin D and fish oil that were somewhat lower than the doses used in other studies, where a better anti-inflammatory effect was found. Nonetheless, the scientists plan to continue monitoring the participants for another two years and study whether vitamin D and fish oil has the potential to prevent autoimmune diseases in young people. The study is published in The British Medical Journal.

Sunshine and vitamin D protect against multiple sclerosis

Multiple sclerosis can result in substantial disability. The chronic inflammation destroys the protective myelin sheath of fat that surrounds nerve fibers. This causes loss of nerves in different parts of the brain and spinal cord, leading to nerve impulse damage. According to a study from University of California and Australian National University, which is published in Neurology, sun exposure and vitamin D during the childhood help protect against sclerosis later in life.

Omega-3 fatty acids counteract rheumatic pain – but only in high doses

Rheumatoid arthritis can result in impaired quality of life and increased mortality. The chronic inflammation destroys peripheral joints and surrounding tissue, eventually resulting in bone erosion and deteriorated articular cartilage. The inflammatory processes can even spread to the organs. British scientists have tested if supplements of omega-3 fatty acids in the form of fish oil supplements can reduce pain in patients with rheumatoid arthritis. It turns out that high-dosed fish oil supplementation has the greatest effect, so it is a good idea to study the label when buying supplements. According to the study that is published in Nutrition, it seems that fish oil in doses of 3-6 grams daily are the most effective. Contrary to anti-rheumatic medicine that comes with serious side effects, fish oil is harmless and even conveys various health benefits.

  • Anti-inflammatory diets and lifestyles have become the new trend
  • There are dozens of useful cookbooks with anti-inflammatory recipes


Jill Hahn et al. Vitamin D and marine omega-3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial. The BMJ 26 January 2022

University of California – San Fransisco. Sunshine may shield children, young adults from MS. ScienceDaily December 8, 2021

Prince Sebastian et al. Association between Time Spent Outdoors and Risk of Multiple Sclerosis. Neurology December 8, 2021

Abdulrazaq, Innes JK, Calder PC. Effect of ω-3 polyunsaturated fatty acids on arthritic pain: A systematic review. Nutrition 2017

Will Chu. Omega-3 oils EPA and DHA differ in actions that tackle inflammation: Study. 08-Dec-2020

About the Vital Study

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