One effect of rising prosperity and the resulting increase in standards of living has been an increase in the consumption of fats. Until very recent times almost all peoples consumed small levels of fat, much of this derived from vegetable and fish oils.
Studies of the geographical prevalence of MS have shown a correlation between this increase in dietary fat and the development and progression of MS. The most important research, however, is the life-long work of Professor Roy Laver Swank of the Swank Multiple Sclerosis Clinic in Portland, Oregon, in the USA.
Professor Swank noted that the incidence of MS seemed to follow the consumption of saturated fat, particularly dairy products, and was lower wherever fish consumption (with its high omega-3 fat content) was high. His studies concluded that dietary fats play a major part in the development and progression of MS. His work has shown that dramatically reducing the intake of saturated fats from all sources can have a great effect on MS.
Beginning in 1949, he enrolled 150 MS patients and commenced them on a very low saturated fat diet. He followed them with meticulous examination and recording of their dietary fat consumption for 34 years. There was no control group who had normal diets, however many of the patients were unable to stick to the diet, allowing comparison between those that did and those that did not. There are also data on relapse rates in MS from many other studies. The results were dramatic. In contrast to the results of other MS patients whose condition had been monitored over time, good dieters did not deteriorate significantly. The results were best for those who started with minimum disability, with 95 per cent surviving and still physically active 34 years later, but regardless of level of disability at entry to the trial the progression of the disease was shown to slow.
Swank continued to follow up the surviving patients of his original study. The most recent publication about these patients provides more insight into the original work.7 The 63 patients surviving at the end of the 34 year study were followed up after a period of 50 years by the time of this review. The great majority of the surviving 63 patients (47) had adhered to the diet; there were only 16 survivors who had not adhered to the diet. For the next 15 years after the original study, they were not seen by Swank, but he attempted to contact them at the end of this period. 15 patients were able to be contacted, interviewed and evaluated, 13 from Toronto, 1 from Portland, Oregon and 1 from Montreal. All 15 had remained on the low saturated fat diet for 50 years. The ages ranged from 72-84. Of the 15, 13 were essentially physically normal and walked without difficulty. The other two required assistance with walking. Swank concluded that if people with MS can rigorously follow the diet, with no more than 10-15g of saturated fat per day, they can expect to ‘survive and be ambulant and otherwise normal to an advanced age’.
Support for a Low Saturated Fat Diet from Basic Science
Scientists at the Hormel Institute and the Mayo Clinic in Minnesota looked at the fatty acid composition of plasma in 14 patients with MS and compared this with 100 patients without MS. The cells of MS patients were comprised of significantly less polyunsaturated fatty acids than those of people without MS. More importantly, these fats had been replaced in the cells by saturated fatty acids. Two other studies have replicated the findings. As yet there has been little further research in this area.
Dietary fats play a major part in the development and progression of MS. Manipulating the intake of fats has a great effect on outcome. According to the work of Swank and others, the potential benefit of a very low saturated fat diet is about a 95% reduction in relapse rate, with stability being achieved at about 3-5 years on the diet.
Dr. Roy Laver Swank in his book, The Multiple Sclerosis Diet Book, advocated the application of a low fat diet as early as possible, recommending a shift in lifestyle from a diet of high-fat foods to one with low-saturated fats and an increase in polyunsaturated oils.
Evidence from basic science suggests that while saturated fat is harmful for people with MS, it is extremely important to avoid altered fats, that is human-refined and human-made fats, as well. In refining oils we basically turn fragrant nut or seed oil extracts into colourless, tasteless, odourless oils which don’t really resemble the original food. Typically this begins with mechanical pressing which can generate temperatures up to 95 degrees Celsius. This involves cooking the nuts or seeds for around two hours at high temperature, then mashing and filtering the oil, and if all that is done, the oil is sold as natural, unrefined oil. Mostly, the oils are then subjected to solvent extraction, in which the oil is treated with powerful acids and alkalis, deodorised and bleached, and sold as pure vegetable oil. By now it is full of trans-fatty acids, cyclic compounds, dimers and polymers not found in nature.
In manufacturing new fats, we convert liquid oils to semi-solid fats in order to prolong their shelf life and allow them to be used in products like biscuits and shortening. These fats are known as hydrogenated fats and trans-fatty acids. Until this century, these fatty acids did not exist in our diets. They are the result of major food processing practices which have transformed our diets. In hydrogenation and trans-fatty acid production, commercial processes heat unsaturated fats to high temperatures in the presence of certain metallic catalysts, and cause chemical changes in the fats to prolong their shelf life or alter their spreadability.
Trans-fatty acids are like mirror images of the original fat, but unlike the original, they are hard, have higher melting points and stick together. As little as 5g a day of trans-fatty acids increases the risk of heart disease by 25%. There are likely to be similar effects on other degenerative diseases. The Australian Consumers Association tested a variety of popular fast foods in 2005. Trans-fats made up from 0.8% to 22.5% of total fats, yet to date, no laws require labeling of the trans-fat content of Australian foods. The effects of all these altered fats in the body arequite unpredictable, although we know they are extremely harmful.
Trans-fatty acids are involved in a wide range of Western diseases such as cancer, heart disease and immune dysfunction. They make cell membranes even more rigid and dysfunctional than saturated fats and are to be avoided at all costs. This means margarine is out, and so are pies, biscuits, and particularly fast foods, like chips and so on. It is important to look carefully at labels. If the words ‘hydrogenated vegetable oil’ or ‘partially hydrogenated vegetable oil’ appear, the product should be avoided. Indeed, ‘vegetable oils’ should be avoided, as they are likely to contain the cheaper saturated vegetable oils like coconut and palm oils. The only freely available oil which is not subjected to the above refining processes, and can be used as a general, all-purpose oil, is extra virgin olive oil. It is called extra virgin because it is made from the first cold pressing of the olives. Virgin olive oil is made from later pressings, and olive oil is refined oil.
These trans-fatty acids and hydrogenated vegetable oils are worse than saturated fats, yet many manufacturers try to pass them off as healthy vegetable oils. Trans-fatty acid and hydrogenated vegetable oils are bad for us in many ways. For a start, the manufacturing process reduces the amount of the good omega-3 and omega-6 fatty acids. They are also bad news for arteries, because of their effects on cholesterol. But most importantly they compete with the essential fatty acids for inclusion in cell membranes, and in making the eicosanoid chemical messengers. Membranes containing trans-fatty acids are like those made of saturated fats; they are even more rigid and less pliable.
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2.Swank RL, Dugan BB. The multiple sclerosis diet book. A low fat diet for the treatment of MS. New York: Doubleday, 1987
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6.Professor Jelinek. Overcoming Multiple Sclerosis (book) & www.overcomingmultiplesclerosis.org
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This is the most traditional source of fat and is largely animal-based. It includes the fat found in meats, butter, cheese and cream. There are also many food products that contain these fats, with cakes, biscuits and pastries being the obvious culprits. Slightly less obvious are items such as barbecued chicken, many sauce mixes, pre-frozen roast vegetables and confectionary bars. Guidelines tell us that we should not exceed 11% of our daily fat intake in this form. It is seen as a bad fat because too much of it will contribute to hardening and narrowing of the arteries.
Unsaturated fats (‘good’ fats)
There are two main kinds of unsaturated fats – monounsaturated and poly-unsaturated. The former come mainly from the oleic acid found in most nuts, avocado pears, rapeseed and olive oils. Monounsaturated fat is believed to lower cholesterol and may assist in reducing heart disease. Like polyunsaturated fat, it provides essential fatty acids for healthy skin and the development of body cells. Polyunsaturates are the essential fatty acids that contain the richest sources of Omega-3 and Omega-6, mainly found in fish oil, sunflower and corn oils and products made from these oils. Polyunsaturates can help reduce the “bad” cholesterol caused by saturated fat. You will find good sources in cold-pressed, unfiltered organic oils such as extra virgin olive oil, flax and rapeseed as well as in fish oils.
Trans fatty acids (TFAs)
Trans fat is created through the process called hydrogenation through which hydrogen is added to vegetable oil . Trans fats are more solid than oil is, making them less likely to spoil. Using trans fats in the manufacturing of foods helps foods stay fresh longer, have a longer shelf life and have a less greasy feel. However TFA’s have been proven to be dangerous to health raising your “bad” (LDL) cholesterol and lowering your “good” (HDL) cholesterol.
The primary health risk identified for trans fat consumption is an elevated risk of coronary heart disease (CHD). A comprehensive review of studies of trans fats was published in 2006 in the New England Journal of Medicine reports a strong and reliable connection between trans fat consumption and CHD. There are also suggestions that the negative consequences of trans fat consumption may go beyond the cardiovascular risk.