How can changing my diet help my arthritis?
Although there are no diets or dietary supplements that will cure your arthritis, some people do find that their symptoms improve as a result of changing what they eat. But because people are all different and there are many different types of arthritis, what works for one person and one type of arthritis may not work for another.
On balance, changing your diet probably won’t have as great an impact on your arthritis as your medical treatments, and we don’t recommend stopping any of your drug treatment without discussing it with your doctor first. But research has discovered several links between arthritis and diet, so it’s still worth thinking about what you eat. The two most important things to think about are:
- your weight – if you’re overweight, losing some weight will reduce the strain on your joints, so you may find you don’t need to take painkillers quite so often.
- whether your diet gives you the vitamins and minerals you need – a good diet can help to protect you against some possible side-effects of drugs and against heart disease (which can sometimes be a complication of certain types of arthritis).
Some forms of arthritis, and some drugs used to treat them are linked with an increased risk of heart and circulatory problems. Several of the diet and lifestyle changes which are useful for arthritis are also useful for heart and circulation health, including exercise and omega-3 fatty acids.
If you have any type of arthritis you should try to eat:
- a balanced and varied diet to get all the vitamins, minerals, antioxidants and other nutrients you need
- a more Mediterranean-style diet which includes fish, pulses, nuts, olive oil and plenty of fruit and vegetables
- more omega-3 fatty acids, for example from oily fish.
You should also exercise regularly.
Why is keeping to a healthy weight important?
The most important link between your diet and arthritis is your weight. Being overweight puts extra strain on weight-bearing joints like your back, knees, hips, feet and ankles. Because of the way joints work, the pressure in your knee is 5–6 times your body weight when you walk so even a small weight loss can make a big difference.
Having too much body fat may also increase inflammation in the body, making your joints more painful. Evidence shows that losing weight can reduce inflammation in any kind of arthritis.
How can I lose weight and eat a healthy diet?
The only way to lose weight and keep it off is to change the way you eat and the amount of exercise you do. You need to balance your food intake against the energy you burn.
The energy in food is measured in kilocalories (kcal), often just called calories. If your diet contains more calories than you use, your body will turn the extra to fat and you’ll put on weight. Most people gain weight gradually often by just eating a few extra calories a day. For example, 100 calories per day more than you burn off will add about 500 g (1 lb) of fat per month. On the other hand, if your food contains fewer calories than you use, your body will burn stored fat and you’ll lose weight.
If you have arthritis you may find it hard to get as much exercise as you did before. And if you’re burning less energy you’re likely to put on weight unless you also reduce your calorie intake.
If you eat fewer calories, it’s important to maintain a balance between different types of food so you don’t lose out on important nutrients. It's important to eat starchy foods like potatoes, rice and pasta. Wholegrain types of rice and pasta are better because they contain more fibre, which is good for bowel health, and they often provide more vitamins and minerals as well. Fruit (but not fruit juices) and vegetables are low in calories but still provide plenty of nutrients.
Cut down on fat
Fat has twice as many calories as the same weight of starch or protein and most people eat far more fat than they need. Eating 30 g (about 1 oz) less fat each day saves 270 calories.
There are four kinds of fats in foods:
- Saturated fats are the most important kind of fat to reduce since they can increase inflammation and pain in the body. These come mainly from animals and are found in:
- full-fat dairy products
- processed foods like cakes, biscuits and pastry
- chips (if fried in animal fat)
- Asian foods, especially those cooked using ghee (clarified butter)
- some vegetable oils such as palm oil or coconut oil.
- Monounsaturated fats are neutral or even useful fats which don’t make inflammation worse. However, they contain just as many calories as saturated fats, so limiting them is important if you're trying to lose weight. These are found in olive and rapeseed oil.
- Trans fats are the worst kind of fat. They're made from oil chemically processed to make it solid and increase its shelf life. They increase cholesterol and are harmful to your circulation and possibly your joints. They're listed on food labels as 'hydrogenated oil' but have mostly been removed from processed foods in recent years.
- Polyunsaturated fats:
- Omega-6 polyunsaturated fatty acids can increase inflammation in the body. You should therefore aim to eat less of these softer fats and oils from corn or sunflower sources.
- Omega-3 polyunsaturated fatty acids are useful in the diet and are found in rapeseed oil, walnuts, free range eggs (depending on the chicken feed), oily fish and fish oil supplements.
To eat less fat you should:
- Avoid 'invisible' fats in foods like biscuits, cakes, chocolate, pastry and savoury snacks, or limit them to special occasions – check the labels.
- Choose lean cuts of meat and trim off any excess fat before cooking.
- Choose fish and poultry more often.
- Use skimmed or semi-skimmed milk.
- Use low- or reduced-fat dairy products (e.g. low fat or diet yogurt, low-fat cheese).
- Use low-fat, olive-oil-based or soya margarines.
- Grill instead of frying.
- Use a very small amount of olive oil if you need to for cooking (if you want to fry foods, use rapeseed oil which doesn’t smoke as much).
- Look for snacks that are naturally low in fat, such as fruit, vegetable sticks, plain popcorn. Small quantities of nuts and seeds provide good fats but don’t appear to cause weight gain.
What vitamins and minerals do I need?
You get most of your vitamins and minerals from the food you eat rather than from supplements. Not having enough (a deficiency) of some vitamins and minerals seems to be linked with arthritis progressing more quickly. The most important vitamins and minerals to think about if you have arthritis are calcium, vitamin D and iron.
Calcium is important for keeping your bones healthy. Calcium deficiency increases your risk of osteoporosis, which causes the insides of bones to be weak, and therefore at risk of breaking. This condition is particularly common in women after the menopause. You may also be at risk of developing osteoporosis if you'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, which causes the outer shell of bones to be soft; this condition can also be known as rickets.
The best sources of calcium are:
- dairy products such as milk, cheese and yogurt – low-fat ones are best, and it doesn't matter if they come from cows or other animals, for example goats
- calcium-enriched milks made from soya, rice or oats
- fish that are eaten with the bones (such as tinned sardines).
Skimmed and semi-skimmed milk contains more calcium than full-fat milk.
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 foods, then you may need a calcium supplement.
Recently there have been worries that taking calcium supplements (but not vitamin D) might have a negative effect on heart health. This seems to apply only to calcium tablets, not calcium from food. Increase the calcium you get from your food or talk to your doctor or a dietitian if you're worried.
Foods and supplements that might help
Research has shown that some foods and food supplements really can help with arthritis, although the effects are fairly specific to the type of arthritis you have. Versus Arthritis has recently funded a grant into a study looking at whether a compound found in broccoli can slow the progression of osteoarthritis, for example.
You may find it helpful to talk your dietary needs through with a nutritionist. You can find a nutritionist in your area at the Nutritionist Resource website.
Omega-3 fatty acids for inflammatory arthritis
Omega-3 (also called ‘n-3’) polyunsaturated fatty acids have been shown to help some people with inflammatory types of arthritis such as rheumatoid arthritis, reactive arthritis, psoriatic arthritis and ankylosing spondylitis. Recent research shows they can help even if you're also taking strong disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate.
What are fatty acids?
Our digestive system breaks down the oils and fats we eat into fatty acids. But other fatty acids cannot be produced in the body and must be obtained from food – these are called essential fatty acids (EFAs). These polyunsaturated fatty acids are divided into two main groups, omega-3 and omega-6.
Omega-3 fatty acids exist in two forms:
- long-chain forms (DHA, EPA) are found in higher levels in oily fish, e.g. pilchards, sardines, mackerel, salmon.
- short-chain forms (ALA) are found in rapeseed oil, flaxseed oil and walnuts.
Omega-6 fatty acids are found in sunflower and corn oils.
The body uses both omega-3 and omega-6 fatty acids to make chemicals called prostaglandins and leukotrienes. The right balance of these helps to control inflammation, and EPA and DHA promote the anti-inflammatory chemicals. Too much omega-6 can increase inflammation in the body but omega-3 fatty acids, especially the long-chain forms EPA and DHA, are thought to be of use in inflammatory arthritis. It’s possible that the short-chain forms may be converted within the body into the long-chain forms that benefit arthritis. However, it's not yet clear whether these are as useful as the long-chain omega-3 fatty acids found in fish oil.
How do I increase my intake of fatty acids?
Research suggests you need at least 2.7 g (2,700 mg) per day of the long-chain omega-3 fatty acids EPA and DHA. In the UK, dietary guidelines recommend eating two portions of fish a week, including one oily. This works out at about 0.45 g per day of omega-3 fatty acids, so you may want to take a supplement to reach the full amount. You can buy supplements from health food shops and some chemists, either in liquid forms or as capsules.
Fish oils act quite slowly so we recommend that you give them at least 3 months’ trial.
Our complementary and alternative medicines report has given fish body oil a score of 5 out of 5 for effectiveness for rheumatoid arthritis, but fish liver oil has only been given a 1 out of 5 for effectiveness in osteoarthritis. We don’t have enough evidence to give a score for fish liver oil for rheumatoid arthritis or fish body oil for osteoarthritis.
Possible side-effects of omega-3 fatty acids
Some people may have mild stomach upsets and diarrhoea from taking high doses of fish oils. If this happens, try taking the supplement with food and/or splitting the total dose into two or three smaller doses per day. If this doesn’t work, try a lower dose, eating more oily fish or a combination of both.
Recently, there have been concerns about a possible link between high levels of omega-3 polyunsaturated fatty acids and prostate cancer. If you’re male and are considering taking high-dose fish oil, you should check with your doctor first.
Caution with fish liver oils
It’s important not to confuse fish body oil with fish liver oil (e.g. cod liver oil and halibut liver oil). Fish liver oils contain omega-3 polyunsaturated fatty acids as well as vitamin D (which helps the body to absorb calcium) and vitamin A.
But it’s dangerous to take fish liver oils in the large doses recommended for arthritis because of the risk of overdosing with vitamin A. This is particularly important for pregnant women, or women who might become pregnant, because vitamin A can harm the unborn baby.
If you’re pregnant, or could become pregnant, you should not take fish liver oils or vitamin A supplements at all. You should only use vitamins designed for pregnancy to make sure you don’t take excess vitamin A.
Adults shouldn’t take more than 3,000 micrograms (µg) of vitamin A per day. If you eat liver, bear in mind that this also contains a lot of vitamin A and will need to be counted as part of your daily intake of vitamin A.
If you want to increase your intake of omega-3 fatty acids, we recommend taking pure fish body oil rather than fish liver oil.
Glucosamine for osteoarthritis
Many people with osteoarthritis try glucosamine, sometimes combined with chondroitin. Joint cartilage normally contains glucosamine and chondroitin compounds, and it’s thought that taking supplements of these natural ingredients may help to improve the health of damaged cartilage.
Research has produced some mixed results but suggests that glucosamine sulphate is more likely to be helpful than glucosamine hydrochloride. If you’re thinking of trying glucosamine we suggest taking 1,500 mg per day of glucosamine sulphate. If you notice an improvement in your joint pain after 3 months you may wish to continue with them. There doesn’t seem to be much extra benefit in taking glucosamine combined with chondroitin.
Glucosamine is available from chemists, health food shops or on the internet. You should avoid internet sites from non-UK organisations, as international safety regulations for supplements can vary.
Possible side-effects of glucosamine
You should bear in mind the following:
- There’s some evidence that glucosamine may increase the level of sugar in the blood, so if you have diabetes be sure to check your blood sugar and talk to your doctor if your readings seem to be higher.
- If you’re taking blood-thinning (anti-coagulants) such as aspirin or warfarin, your blood-thinning control may be affected, so make sure you have your regular blood checks and again discuss this with your doctor.
- Glucosamine is often made from shellfish. If you’re allergic to shellfish make sure you take a vegetarian or shellfish-free variety.
Should I avoid certain foods?
Some people feel that certain foods are bad for arthritis and that cutting them out helps. These foods include:
- citrus fruits, such as oranges, lemons and grapefruit
- vegetables from the nightshade family (solanaceous plants) including potatoes, tomatoes, peppers, chillies and aubergines.
We don’t recommend leaving these fruits and vegetables out of your diet because of the important nutrients they contain. There’s no scientific evidence that cutting out these foods can help with arthritis. In fact, they're rich in antioxidants – oranges and red peppers contain an antioxidant called β–cryptoxanthin which studies have shown may slow down the progression of arthritis.
Fasting for rheumatoid arthritis
Fasting for short periods can bring a short-term improvement in the symptoms of rheumatoid arthritis, although they quickly return once you go back to a normal diet. We don’t recommend fasting as a treatment for arthritis. However, if you do wish to try it, it should only be done for one day at a time and under expert supervision.
What about food allergies?
Some people are allergic to certain foods such as peanuts or shellfish. Allergic reactions occur quickly after the food is eaten and there’s no real evidence that food allergies are relevant to the development of arthritis or its treatment.
Some people are also intolerant of certain foods. Symptoms of food intolerance develop fairly slowly after eating a food – after hours or even days. So food intolerances can be difficult to identify without the help of an expert.
Research has shown that some people have an improvement in their symptoms if they cut out particular foods. The reasons for this aren’t yet clear and the foods involved vary from person to person. Some books even suggest diets which cut out nutritionally important food and could leave your body short of important vitamins and minerals if you followed them for a long time.
The only way to be sure that you have a food intolerance is by dietary 'exclusion and challenge' where you leave out a certain food from your diet, for a period of at least a month. This is followed by a ‘challenge’, where you reintroduce the food to see if it causes a reaction. If your arthritis is related to a food allergy you’ll notice a flare-up of your symptoms within a few days. It's important to cut out each food you're testing completely and reintroduce them one at a time. We recommend that you speak to a registered dietitian who can make sure you’re excluding foods completely and check that you’re not excluding important nutrients.
Do vegetarian or vegan diets help?
Some studies have shown that people who eat a lot of red meat have a higher risk of developing inflammatory types of arthritis. And vegetarian diets have been shown to be helpful in the long term for some people with rheumatoid arthritis. A vegan diet, which doesn’t include any meat, fish or other animal products, may also be helpful – possibly because of the types of polyunsaturated fatty acids included in the diet.
If you eat a vegan diet it's important to make sure you get all the nutrients you need, particularly calcium, vitamin B12, vitamin D and selenium.
Calcium is present in leafy green vegetables (e.g. cabbage, kale, broccoli), watercress, beans and chickpeas, and some nuts, seeds and dried fruits. Calcium is often added to white bread and to some soya milks, oat and rice milks – check the label.
Vitamin B12 is also commonly added to soya milk, and yeast extract is another good source. Many vegan foods are fortified with B12.
Selenium can be found in Brazil nuts and is often included in multi-vitamin supplements.
Vitamin D isn't naturally present in many foods, especially if your diet is vegan. However the body naturally produces it when the skin is exposed to the sun. If you're dark-skinned or prefer to keep your skin covered, then look for vegetable milks or margarines which have vitamin D added. Shiitake mushrooms also provide some vitamin D, or you may need to consider taking a supplement – vegan supplements are available. Aim for 10–25 micrograms (μg) depending on whether you go out in the sun often or not.
Foods and supplements that are unlikely to help
Some people with arthritis find that cider vinegar and honey ease their symptoms, although there’s no scientific evidence to show that they’re helpful. But there’s no reason why you shouldn’t try it if you want to.
MSM (methylsulphonylmethane) is a sulphur-containing substance that has been recommended for various health problems, including arthritis. However, there’s no strong evidence to support the effectiveness of MSM for treating symptoms of arthritis.
CMO (cetylmyristoleate) is a waxy substance made from beef fat, which some people claim can help arthritis. Again, there’s little scientific evidence that it does so.
How can changing my diet help with gout?
Gout is a condition caused by a high level of urate in the body. Urate can form crystals in the joints, causing sudden attacks of severe pain and inflammation. Making the following changes to your diet and lifestyle can help to reduce the levels of urate in your body:
- Lose weight if you’re overweight as this can reduce urate levels in the body. It must be done gradually. Extreme weight loss or fasting can actually raise urate levels because it speeds up the breakdown of cells in the body.
- Drink less alcohol, especially beer, as drinking too much alcohol is often linked with gout. If you have gout you should aim to keep your alcohol intake to around 1–2 units a day.
- Drink plenty of water to avoid becoming dehydrated and to help to ‘flush out’ excess urate and prevent it from crystallising in the joints. You should drink at least 1 litre (about 2 pints) of non-alcoholic fluids per day, or up to 3.5 litres (about 6 pints) if you have kidney stones.
Drinking sugar-sweetened soft drinks and fructose-rich fruits and juices may be linked with an increased risk of gout. Diet soft drinks don’t appear to increase the risk.
Foods that contain a lot of purines may play a part in the build-up of urate, so cutting down on purine-rich foods may be helpful. Aim to reduce the amount of protein you get from meat – for example, by eating one less portion of meat or fish per day. This can be replaced by other sources of protein, such as beans, eggs, pulses or low-fat dairy products.
Urate levels aren’t affected by acidic fruits and there’s some evidence that higher vitamin C intake can help to reduce the risk of gout attacks. So you can include fruits like oranges and grapefruit in your diet. There’s some evidence to suggest that cherries (as fruit or juice, fresh or preserved) may be helpful, and that drinking a glass of skimmed milk every day can help to prevent acute attacks of gout.