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The impact of food groups – the good, the bad and the ugly


By Dr Joanna McMillan

The links between various dietary factors and the progression of MS remain debated by scientists and doctors working in the field. However, a picture is emerging and it is clear that certain dietary patterns and foods do indeed influence the development and progression of the disease.

The good news is that the kinds of changes that seem to be good for slowing the progression of MS are in line with what we know to be good for overall health. So in essence you have nothing to lose in trying to adjust your diet in this way and you may just find you benefit from increased vitality, far less fatigue and a slowing of the progression of your symptoms.


Reduce your intake of saturated fat

One of the main areas of interest has been in the amount and types of fat in the diet. When studies have compared the incidence of MS between countries, they have noted that in those countries where a typical Western style diet is consumed the incidence of MS is higher than in developing nations with typically low fat diets. Of interest Japan, although a developed nation, has maintained a low fat traditional diet and also has a lower incidence of MS than Western countries.

Now of course there are many differences between the diets and lifestyles of countries so this is not proof that fat is to blame. However, these observations led to further work to try to establish a dietary link. The most important research has come from Professor Roy Laver Swank who has studied diet and MS since the late 1940s. Professor Swank noted that the incidence of MS was higher in those that consumed a more saturated fat and far lower in those that consumed lots of fish high in omega-3 polyunsaturated fats.

He then went on to treat patients with MS by putting them on a very low saturated fat diet. Some of his patients have now been studied for over 50 years and the data compiled continues to play an important part in understanding how diet might affect MS. There have been some criticisms of his work, but for the most part the work of others and the understanding of plausible biological mechanisms, has backed up his findings.

Saturated fats are found in the highest amounts in animal fats such as fatty meats, full fat dairy products and in the tropical oils from coconut and palm. These are the types of fats that we have typically been advised to reduce our intake of in relation to heart health. Although that is now a controversial area in itself, much of the apparent inconsistencies may be explained by the fact that many cut these fats out and replaced them with low fat foods high in refined starch and/or sugar. This is just as bad if not worse for heart health.

There are reasons why a high saturated fat diet could potentially worsen MS. Saturated fats are used to make various inflammatory factors in the body, they alter the balance of bacteria in the gut towards a less healthy balance and this in turn affects immune function. Finally, saturated fats are less fluid than unsaturated fats (hence they are solid at room temperature) and once incorporated into cells this lower fluidity affects the way the cell functions.

There is one other type of fat that is without doubt the worst type of fat for anyone to consume in their diet and that is trans fat. Trans fats do not occur to any great extent in nature, but they are produced in food manufacturing when a liquid oil is hydrogenated to make it behave more like a saturated fat – and thus more stable. Trans fat is known to increase heart disease risk and for this reason health authorities around the world are introducing stronger legislation to try to get rid of these fats from our food. Although there is currently no direct link to MS, for overall health you are best to avoid these fats. Read the ingredients list of any packaged foods you buy and if you see the terms “hydrogenated vegetable oil” or “partially hydrogenated vegetable oil” put the product back. They are also produced during prolonged heating and repeat heating of oils, so fried fast foods and fries are also a potential source. Try to minimise your consumption of these foods.


Eat more omega-3 fats

You remember Professor Swank also noted that those eating lots of fish had a lower incidence of MS. Well interestingly the omega-3 polyunsaturated fats found in oily fish and seafood are the precursors for anti-inflammatory factors in the body. They have a high concentration in the brain and known to be especially important for brain function. Omega-3s have been shown to be helpful in treating several inflammatory diseases and may well help to reduce the progression and symptoms of MS.

You will also find omega-3 fats in some plant foods including flaxseed (also called linseed), walnuts and chia seeds. These may also be helpful, however it’s important to note these are shorter chain omega-3s and not the same as the long chain omega-3s found in seafood. Since these plant foods are nutritionally rich in many nutrients, they are nevertheless worthwhile including in your diet. Just be sure to eat seafood as well, or consider taking an omega-3 supplement.


Choose extra virgin olive oil

Extra virgin olive oil is the best quality cold pressed oil from the olive and is not refined in any way. It has a wealth of health benefits. It contains several antioxidants that have roles in protecting cells in the body. It is primarily monounsaturated fat – this makes it stable for cooking and in the body, but also allows you to absorb and make use of the omega-3 fats in your diet at the same time. Plus, it’s at the heart of the Mediterranean Diet, known to reduce inflammation while also reducing the risk of cardiovascular disease.


Eat less added sugar and refined starch, choosing high fibre foods instead

When carbohydrates occur in plant foods they are almost always (with the notable exception of honey) accompanied by fibre. When we consume carbohydrates in this way the fibre slows down our digestion and absorption of the resultant sugars, it helps us to manage our blood glucose levels and we need less insulin to deal with them once absorbed. The fibre then has a further benefit further down the gut where it fuels the ‘good’ bacteria, encouraging their growth so that they in turn keep down the levels of potentially ‘bad’ bacteria.

In MS these effects are important. High blood glucose and insulin levels are pro-inflammatory, while the gut microbiome has a strong influence on immune function.

Unfortunately, many modern foods are made with sugar and/or white flours. These are essentially extractions of the plant to concentrate the carbohydrate and get rid of the fibre. This not only affects their nutrition but it also results in foods that are highly palatable, energy dense and very easy to overeat. Eating too many kilojoules is in itself harmful for all of us, but potentially also negatively affects the progression of MS.

By avoiding such foods, but including more plant foods in a form closer to their whole natural form, you benefit from the energy providing carbohydrates, while gaining the protection of the fibre. This means more wholegrains, legumes, vegetables and whole fruit.


Putting it into practise
  • Eat less red meat and when you do have it choose lean cuts and a small portion.
  • Opt for poultry or seafood more often.
  • Choose oily fish such as salmon, trout, sardines and mackerel at least twice a week, more often if possible.
  • Sprinkle chia, flaxseeds or walnuts onto your muesli, porridge or over a salad. Try a soy and linseed sourdough bread.
  • Avoid deep fried fast foods such as fries and battered meat or fish, as well as commercial pastries and pies.
  • Fill at least half your plate with vegies and enjoy as great a variety of types as you can – the more different colours the better
  • Choose wholegrains and legumes more often, while avoiding products high in added sugars or based on white flour
  • Avoid sugar-sweetened drinks and fruit juices.
  • Choose low fat dairy products.
  • Opt for the good fats found in extra virgin olive oil, avocado, nuts and seeds.
  • Avoid overeating and maintain a healthy weight.