As a physical therapist, many of my patients have arthritic disease of the joints. During my traditional education I received minimal education related to the importance of vitamin D and calcium except that they are important for bone strength, and deficits are in part what lead to osteoporosis (thinning of the bones). However, I am interested in what role vitamin D and calcium play in arthritic conditions, and if there is a link to joint health and vitamin D and calcium.
First, let’s look at these two separately for what they each do, where they come from and what happens if you don’t have enough.
Vitamin D, specifically vitamin D3 in it most natural form is synthesized from cholesterol in the presence of sunlight. Without sunlight, the body does not produce vitamin D. Vitamin D is necessary for calcium absorption, which means it operates more like a hormone than a true vitamin. Vitamin D comes in limited amounts in food sources. The richest sources outside of sunshine of vitamin D are butterfat, eggs, liver, organ meats, marine oils and seafood like shrimp and crab. 1 Deficiency of vitamin D has been linked to osteopenia (bone loss), osteoporosis (severe bone loss resulting often in fracture), cancer, Type 1 Diabetes, Multiple Sclerosis, and even cardiovascular disease. 2,3 In addition to these diseases vitamin D deficiency has been linked to many other disease like early inflammatory arthritis (a precursor to rheumatoid arthritis) 4, osteoarthritis of the knee 5, and autoimmune disease like systemic lupus erythematous (SLE), rheumatoid arthritis (RA) and type 2 diabetes (T2DM) 6. Vitamin D status can even be used as a predictor of prognosis for patients with acute ischemic stroke. 7 Vitamin D is clearly not only important for bone strength but also joint health, metabolic health, and even brain health.
Calcium is a mineral that is readily available in dairy products including cheese, milk and yogurt and bone broth (especially broth made with long marrow bones). In these forms, the calcium is most readily absorbable. The calcium available in meats, vegetables and grains is difficult to absorb due to presence of iron and zinc. They the phytic acid present in grains, if not properly soaked, fermented sprouted, will bind the calcium making it less available for absorption. Deficiency of calcium has been linked to hypertension (high blood pressure), colon cancer, osteoporosis, osteomalacia and rickets. 2
Vitamin D AND calcium work together to produce strong bones, teeth, and normal growth. Vitamin D is required to absorb calcium. Without one or the other you miss vital ingredients for making bones strong. So it is important to meet if not exceed the RDA (Recommended Daily Allowances) recommendations for both in order to maintain and improve bone health, and even prevent joint diseases.
This table below summarizes the average daily amount of each needed to prevent disease. 8
Another recommendation is based on the Optimum Daily Intake (ODI), or what is required not just for disease prevention but also for optimal general health. This states that for an adult male or female these are the daily requirements (sorry it changes units from the above table): 2
Vitamin D: 1,000 IU
For treatment of disease, those dosages are even more 2:
Vitamin D: 2,000 IU
Always, it’s best to get these in natural form. For vitamin D, one would have to increase full solar spectrum sun exposure to a large portion of the skin (think tank top and shorts), which is called Heliotherapy. The amount of sun exposure needed is moderate and less than the time required to produce sunburn. 3 There is no finite answer on the exact amount if time needed because it depends on your skin tone, your age, time of day and where you live. But a general rule of thumb is that the darker your skin color, the longer time you need in midday sun versus fair skin may only be 3-8 minutes to produce 400IU. 9 So one would need to be exposed to sun at least 2-3 times ar that rate to result in 1200 IU vitamin D. And if you are unable to meet those requirements either due to lifestyle or injury or illness, then it may be necessary to supplement with vitamin D3 (cholecalciferol), as other forms are less bio-available for absorption. And of course, eating foods high in vitamin D like fish oils, and fatty saltwater fish such as sea bass, halibut, swordfish, herring, tuna, cod and sable. Even sardines which have not only vitamin D but also calcium because you are eating the tiny bones.
I logged a sample day of meals into a nutrition program to assess the nutrient summary where I incorporated dairy, fish and even organ meat to see if I met the adequate dosages of vitamin D and calcium based on the RDA. Unfortunately, the day of meals did not meat the minimum requirements for either vitamin D or calcium, not even close.
Although I didn’t meat the RDA requirements with my diet I did spend time in the sun wearing a bathing suit. There was no place in the system for me to enter sun exposure for assessing my vitamin D levels based on this sun exposure.
What does this mean?
For me it means that if you have a personal history or family history of any of the above joint diseases, cardiovascular disease or osteoporosis, then you should most definitely speak to your health care provider about possible supplementation of Vitamin D3 and Calcium in addition to getting full spectrum sun exposure without sun block regularly.
Remove. Replace. Restore.
Remove heavily refined and processed foods, they are nutrient depleting and it is difficult to meet vitamin D and calcium with food alone. Remove fear of the sun.
Replace with nutrient rich whole foods, especially saltwater fish and even bone broth. Supplementation should your medical or family history require it, as a preventative strategy. Spend time outside in the sunshine, in a bathing suit. Don’t burn, but expose the cholesterol under your skin to the sunrays to make vitamin D. Healthy exercise is also critical to bone and joint health even without adequate vitamin D and calcium.
Restore bone health and even improve joint health too.
Eat well. Move well. Sleep well. Thrive on.
1. Fallon S, Enig M. Nourishing traditions; the cookbook that challenges politically correct nutrition and the diet dictocrats. Brandywine, MD: NewTrends Publishing, Inc; 2001.
2. Lieberman S, Bruning N. The real vitamin and mineral book. New York, New York: The Penguin Group; 2007.
3. Baggerly CA, Cuomo RE, French CB, et al. Sunlight and vitamin D: Necessary for public health. J Am Coll Nutr. 2015;34(4):359-365.
4. Park YE, Kim BH, Lee SG, et al. Vitamin D status of patients with early inflammatory arthritis. Clin Rheumatol. 2015;34(2):239-246.
5. Sanghi D, Mishra A, Sharma AC, et al. Does vitamin D improve osteoarthritis of the knee: A randomized controlled pilot trial. Clin Orthop Relat Res. 2013;471(11):3556-3562.
6. Broder AR, Tobin JN, Putterman C. Disease-specific definitions of vitamin D deficiency need to be established in autoimmune and non-autoimmune chronic diseases: A retrospective comparison of three chronic diseases. Arthritis Res Ther. 2010;12(5):R191.
7. Park KY, Chung PW, Kim YB, et al. Serum vitamin D status as a predictor of prognosis in patients with acute ischemic stroke. Cerebrovasc Dis. 2015;40(1-2):73-80.
8. McGuire M, Beerman K, eds. Nutritional sciences; from fundamentals to food. Third Edition ed. Wadsworth; 2013.
9. Terushkin V, Bender A, Psaty EL, Engelsen O, Wang SQ, Halpern AC. Estimated equivalency of vitamin D production from natural sun exposure versus oral vitamin D supplementation across seasons at two US latitudes. J Am Acad Dermatol. 2010;62(6):929.e1-929.e9.
Dr Carolyn Dolan DPT, Cert MDT, MSHN
Where physical therapy, nutrition and lifestyle meet, because how you live your life determines whether or not you soar. Inspiring action with information so you can reduce pain, optimize healing and improve function naturally during recovery from injury, surgery or painful condition. This is a website for the open-minded; obstinate need not apply.