You may have heard that supplementing with vitamin D and omega-3s may prevent disease and decrease mortality (13). The National Health and Nutrition Exam Survey from 2005-2006 showed around 41% of people (11) in the United States were deficient in vitamin D, and the ratio at which Americans consume omega 6 fats to omega-3 fats is 20:1 (12). A recent study showed that obesity may be decreased by increasing the amount of omega-3s consumed and that a balance of omega-3 and omega-6 is crucial (12). Let’s get into the proposed benefits of supplementing these two.
vitamin D
We have all heard that it is important to go outside every day to get our vitamin D. According to Yale Health, vitamin D helps absorb calcium from the small intestine which is crucial for cell and bone health.
There are 2 kinds of vitamin D, D2 and D3. D2 occurs from UV irradiation of the yeast sterol ergosterol and is found in foods like mushrooms. D3 is obtained when UVB light is exposed to the skin which helps the body synthesize D3 from cholesterol (7).
Vitamin D is crucial because without it, the body is only able to absorb 10-15% of calcium consumed through diet and 60% of phosphorus.
Along with decreasing mortality, vitamin D has been shown to help prevent cancer, heart disease, fractures and falls, autoimmune diseases, influenza, type-2 diabetes, and depression (7).
Research has shown that only in the fall, spring and summer is the sun strong enough to allow the body to use sunlight to convert UVB to vitamin D so supplementation is most likely necessary. Even during the summer months, sunscreen reduces vitamin D synthesis by 95% (7).
omega-3 fatty acids
Omega-3 fatty acids include unsaturated fatty acids that have at least one double bond. The fats include a-linolenic acid or ALA, eicosapentaenoic acid or EPA and docosahexaenoic acid or DHA. Omega-3 fatty acids can be found naturally in fish, seeds, nuts, green leafy vegetables and beans. Omega-3 fatty acids have been found to lower triglycerides but the mechanism is still not fully understood. It is thought that omegas may help lower triglyceride levels, increase beta-oxidation of fatty acids, increase the expression of lipo-protein-lipase (LPL), and could influence total body lipid accretion (14).
autoimmune disease
Many studies have been conducted showing the benefits of supplementing vitamin D along with omega-3 fatty acids. A recent study conducted with over 25,000 participants for over 5 years tested if supplementing with vitamin D and omega-3s reduced autoimmune disease. The study found that by taking vitamin D, with or without omega-3s, autoimmune disease was reduced by 22%. The study also found that those taking omega-3s, with or without vitamin D, reduced autoimmune disease by 15%, though this was not considered statistically significant by the investigators (1).
women: PCOS & GDM
In a study from 2018 over 12 weeks, supplementing both vitamin D and omega-3s was shown to decrease testosterone levels, anxiety, depression and stress. Supplementation was also shown to reduce C-reactive protein which is an inflammatory indicator that can show signs of future disease. Supplementing increased plasma antioxidant capacity allowing more antioxidants to enter the blood and downregulated the gene expression of interleukin-1 while upregulating vascular endothelial growth factor in those with PCOS (3) The study came to the conclusion that co-supplementing had beneficial effects on mental health. Another study found that supplementation improved sleep quality along with depression and anxiety in those who are of reproductive age with pre-diabetes and vitamin D deficiency (2).
In women with gestational diabetes mellitus (GDM) (diabetes during pregnancy), who were supplemented with vitamin D and omega-3s for 6 weeks were able to decrease their fasting blood glucose, fasting insulin, insulin resistance, triglycerides and cholesterol (5). At the same time, output from beta cells, or cells that produce insulin, was increased. The study concluded that after 6 weeks of supplementing with vitamin D and omega-3s, patients can reduce blood sugar and blood lipids and ultimately improve glucose and lipid metabolism (5).
bottom line
In all, the evidence is clear that there may be health benefits to supplementing with Omega-3s and vitamin D. A deficiency in vitamin D can lead to malabsorption of calcium and phosphorus and increase the rate of mortality. So by adding foods with omega-3s (chia seeds, hemp seeds and flax seeds) to a morning smoothie, and making sure to incorporate vitamin D containing foods (salmon, sardines, tuna, and foods fortified with vitamin D), you will be promoting your overall health.
It is recommended that with supplementing vitamin D, have levels checked periodically to ensure the proper dosage as requirements are highly individualized. Vitamin D is a fat soluble vitamin, which means it is stored in the body’s fat tissue and liver, so there is potential for overdose and toxicity, though rare. The same goes for omega-3 supplementation.
It is also worth noting that there are not a proliferative amount of studies with regard to vitamin D and omega-3 supplementation. While the results are promising, know that more research needs to be done.
this post was co-written by nutrition enthusiast and nutrition student, Ashley Lyons
References
Hahn J, Cook NR, Alexander EK, Friedman S, Walter J, Bubes V, Kotler G, Lee IM, Manson JE, Costenbader KH. Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial. BMJ. 2022 Jan 26;376:e066452. doi: 10.1136/bmj-2021-066452. PMID: 35082139; PMCID: PMC8791065.
Rajabi‐Naeeni, Masoumeh, et al. “Effect of omega‐3 and vitamin D co‐supplementation on psychological distress in reproductive‐aged women with pre‐diabetes and hypovitaminosis D: A randomized controlled trial.” Brain and Behavior 11.11 (2021): e2342.
Jamilian M, Samimi M, Mirhosseini N, Afshar Ebrahimi F, Aghadavod E, Talaee R, Jafarnejad S, Hashemi Dizaji S, Asemi Z. The influences of vitamin D and omega-3 co-supplementation on clinical, metabolic and genetic parameters in women with polycystic ovary syndrome. J Affect Disord. 2018 Oct 1;238:32-38. doi: 10.1016/j.jad.2018.05.027. Epub 2018 May 26. PMID: 29859385.
Rajabi-Naeeni M, Dolatian M, Qorbani M, Vaezi AA. Effect of omega-3 and vitamin D co-supplementation on psychological distress in reproductive-aged women with pre-diabetes and hypovitaminosis D: A randomized controlled trial. Brain Behav. 2021 Nov;11(11):e2342. doi: 10.1002/brb3.2342. Epub 2021 Sep 2. PMID: 34473420; PMCID: PMC8613419.
Huang S, Fu J, Zhao R, Wang B, Zhang M, Li L, Shi C. The effect of combined supplementation with vitamin D and omega-3 fatty acids on blood glucose and blood lipid levels in patients with gestational diabetes. Ann Palliat Med. 2021 May;10(5):5652-5658. doi: 10.21037/apm-21-1018. PMID: 34107720.
Jamilian M, Samimi M, Ebrahimi FA, Hashemi T, Taghizadeh M, Razavi M, Sanami M, Asemi Z. The effects of vitamin D and omega-3 fatty acid co-supplementation on glycemic control and lipid concentrations in patients with gestational diabetes. J Clin Lipidol. 2017 Mar-Apr;11(2):459-468. doi: 10.1016/j.jacl.2017.01.011. Epub 2017 Feb 2. PMID: 28502503.
Nair R, Maseeh A. Vitamin D: The “sunshine” vitamin. J Pharmacol Pharmacother. 2012 Apr;3(2):118-26. doi: 10.4103/0976-500X.95506. PMID: 22629085; PMCID: PMC3356951.
Sutherland, J. P., Zhou, A., & Hyppönen, E. (2022). Vitamin D Deficiency Increases Mortality Risk in the UK Biobank. Annals of Internal Medicine. https://doi.org/10.7326/m21-3324
Shahidi, F., & Ambigaipalan, P. (2018). Omega-3 Polyunsaturated Fatty Acids and Their Health Benefits. Annual Review of Food Science and Technology, 9(1), 345–381. https://doi.org/10.1146/annurev-food-111317-095850
Sizar O, Khare S, Goyal A, Givler A. Vitamin D Deficiency. 2022 Jul 27. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan–. PMID: 30335299.
Forrest KY, Stuhldreher WL. Prevalence and correlates of vitamin D deficiency in US adults. Nutr Res. 2011 Jan;31(1):48-54. doi: 10.1016/j.nutres.2010.12.001. PMID: 21310306.
Simopoulos AP. An Increase in the Omega-6/Omega-3 Fatty Acid Ratio Increases the Risk for Obesity. Nutrients. 2016 Mar 2;8(3):128. doi: 10.3390/nu8030128. PMID: 26950145; PMCID: PMC4808858.
Pilz, Stefan, et al. “Vitamin D and mortality.” Anticancer research 36.3 (2016): 1379-1387.
Novotny, Kristina, Kristina Fritz, and Mayur Parmar. “Omega-3 Fatty Acids.” (2020).
