Vitamins and minerals

Deficiency in some vitamins and minerals seems to be associated with arthritis progressing more quickly. Below is an explanation of key vitamins and minerals and how they can affect your arthritis if you aren’t including enough of them in your diet.

Calcium

Calcium is important for maintaining healthy bones. Calcium deficiency increases your risk of osteoporosis, which is particularly common in women after the menopause. Many people with arthritis also have a risk of developing osteoporosis, especially if they’re taking steroids on a long-term basis. A lack of calcium in your diet can also increase your risk of developing a condition called osteomalacia.

The best sources of calcium are:

• dairy products such as milk, cheese, yogurt (low fat ones are best – skimmed and semi-skimmed milk contains more calcium than full-fat milk)
• calcium-enriched varieties of milks made from soya, rice or oats
• fish that are eaten with the bones (such as sardines).

We recommend a daily intake of calcium of 1,000 milligrams (mg), with added vitamin D if you’re over 60.

If you don’t eat many dairy products or calcium-enriched substitutes, then you may need a calcium supplement. We recommend that you discuss this with your doctor or a dietitian. 

Vitamin D

Your body needs vitamin D to absorb and process calcium, and there’s some evidence that arthritis progresses more quickly in people who don’t have enough vitamin D.

Your body produces vitamin D when your skin is exposed to sunlight, so a slight deficiency is quite common in winter. You can also get vitamin D from your diet or supplements such as fish liver oil.

If you're over 60, dark-skinned or don't expose your skin much to the sun and are worried about a lack of vitamin D, you and your doctor should discuss whether a vitamin D supplement would be right for you.

Iron

Iron is important in preventing anaemia and many people with arthritis are anaemic. Non-steroidal anti-inflammatory drugs (NSAIDs) help the pain and stiffness of arthritis but may cause bleeding and stomach ulcers in some people, leading to anaemia. The other main cause of anaemia in arthritis is anaemia of chronic disease, which often occurs with rheumatoid arthritis and similar conditions and doesn’t improve with iron supplements. If you’re anaemic your doctor can tell you if more iron is likely to help.

Good sources of iron are:

• red meat
• oily fish e.g. sardines
• pulses e.g. lentils and haricot beans
• dark green vegetables e.g. spinach, kale and watercress.

Your body absorbs iron better if you take it with vitamin C, so have fruit juice or a good portion of fruit or vegetables with your meal. It’s best not to drink tea with your meal as this reduces the amount of iron that your body can absorb.

Vitamin C

Poor vitamin C intake has been linked with arthritis. However, if you make sure you have your five portions of fruit and vegetables a day, then you’re unlikely to have a problem with vitamin C and shouldn’t need supplements.

Selenium

Mild selenium deficiency is quite common in the UK and may be associated with more rapid progression of arthritis. The richest natural source of selenium is Brazil nuts, but meat and fish also contain some. Selenium is nearly always included in antioxidant supplements which you can buy in chemists and health food shops.