Multiple sclerosis

Multiple sclerosis (MS) is a disease affecting the central nervous system (the brain and spinal cord). In MS, the protective sheath called myelin, that surrounds the nerve fibres of the central nervous system becomes damaged. This disrupts the messages that pass between the brain and other parts of the body. Symptoms include blurred vision, paralysis, slurred speech, lack of coordination and incontinence. The severity of symptoms depends on how much damage has occurred.

Around 85,000 people in the UK have MS and twice as many women as men are affected. It can occur at any age, but in most cases symptoms appear between the ages of 20 and 40. Most people with MS suffer attacks followed by periods of recovery. This is why MS is called a relapsing-remitting condition. It is a lifelong condition, but it is not terminal and people with MS can expect to live as long as anyone else.

MS is an autoimmune disease whereby the body’s immune system attacks its own tissues. As with other autoimmune diseases (like rheumatoid arthritis or type 1 diabetes), it is thought that a combination of genetic factors and environmental triggers cause the disease.

Although genes are involved, evidence suggests that MS is more strongly related to environmental factors which may include bacteria, viruses or components of the diet.

Geographical pattern

One of the most interesting features of MS is that it occurs mostly in countries far from the equator. It is relatively common in the UK, North America and Scandinavia, but rare in Malaysia and Ecuador. The reason for this is not really understood; it could be that MS is triggered by a bacteria or virus which thrives in cooler climates. Alternatively, it could be that certain foods eaten in these countries are responsible.

Populations that eat lots of animal-based foods are most affected by MS. In fact, many studies reveal a striking link between the geographical pattern of MS and that of meat and dairy food consumption. In general, the evidence shows that foods rich in saturated fats are associated with higher levels of MS, while foods rich in polyunsaturated fats are linked to lower levels.

Omega-6 fatty acids and MS

Omega-6 fats may be involved in both the development and treatment of MS. This may be because people with MS do not process them as well, leading to lower levels than in people without MS.

Studies show that taking borage oil (containing the omega-6 fatty acid GLA) can lower the number of relapses and slow the disease. Some experts argue that it would be good for people with MS to add more omega-6 fats to their diets. Others disagree saying that the evidence is not there and it should be avoided because of the potential negative health consequences.

An ideal way of getting enough (but not too much) omega-6 is through increasing flaxseed oil in the diet, as it contains both omega-6 and omega-3 fatty acids. Some experts recommend consuming four teaspoons of flaxseed oil daily (higher than the 1-2 teaspoons-a-day recommended normally). In general, a low saturated fat, plant-based diet, containing both omega-6 and omega-3 fats in a healthy balance may help control MS.

Autoimmune diseases

In general, diets low in saturated fat and high in omega-3 fats can reduce the severity of some autoimmune diseases such as rheumatoid arthritis, while diets high in omega-6 fats may increase the severity. The possible exception is MS; there is convincing evidence for a protective role of both omega-6 and omega-3 fats in MS.

The immune system works best when there is a good balance of omega-6 and omega-3 fats in the diet. The optimum ratio varies depending on age and the condition being treated. Some scientists recommend ratios between 5:1 and 10:1 omega-6 to omega-3. Others suggest a ratio of between 1:1 and 4:1 as being best. What are we getting? The current ratio in our diet is estimated to be higher than 15:1 and may be as much as 30:1 in some people. We clearly need to increase our intake of omega-3s.

You can improve your ratio by making a few simple changes: use olive oil in place of sunflower or safflower oil, and flaxseed oil in dressings and dips. If you want to improve the ratio further, take flaxseed oil or an algal supplement.

The overall message is clear: a plant-based diet low in saturated fat, salt and sugar (and processed foods) and high in fresh fruits, vegetables, wholegrain foods, pulses, nuts and seeds can provide all the nutrients required for good health while protecting against a wide range of diseases.

As the incidence of most autoimmune diseases is directly linked to the consumption of animal foods, this approach could help prevent many autoimmune conditions that occur increasingly in populations that eat large amounts of dairy and meat products.