Poly unsaturated fats bad for your health?

Shocker! Research out recently demonstrates that higher intakes of omega 6 fats are linked to bowel disease. Could everything you understand about ‘good fats’ and ‘bad fats’ be wrong?

Yet again new information highlights the fact that though food producing companies use the potential benefits of  certain nutrients as a selling point,  the truth is usually far more complex…..

Poly unsaturated fats (think omega 6, omega 3, fish and flax oils etc) have been pushed and pushed on the strength of their health benefits. Encouraging effects on heart, brain and joint health and been demonstrated but there’s also information that you don’t hear a huge amount about. Much of it surrounds omega 6 in particular.

THIS article on the BBC highlights the findings of a group of multinational group of researchers looking at the effects of different levels of dietary fats. They found that high intakes of certain poly unsaturated fats could have a severe impact upon  gut health. In a sentence:

‘Those with high intakes of omega 6 polyunsaturated fats were almost twice as likely to develop ulcerative colitis’

In fact some of the conclusions were startling;

An estimated 30% of cases could be attributed to having dietary intakes higher than the lowest quartile of linoleic acid intake.

Startling but not completely unexpected. Why? Below we’ll look at the why’s and hows:

Again science reporting is a blunt instrument and the reporting of nutrition news is one of the worst offenders. However this article did include some useful info towards the end of the article mentioning both the issues of omega 3 intake and whole diet.

The issues are these bullet pointed for speedy reading

• Omega 6 & omega 3 are both essential fatty acids: we HAVE to eat them
• Omega 6 is pro inflammatory omega 3 anti inflammatory
• Too much omega 6 will probably leave you more vulnerable to a range of conditions associated with inflammation
• Omega 6 is eaten in large quantities in today’s diet (found in grains & things fed of grains e.g. cows)
• Omega 3 is rather lacking in our diets

So polyunsaturated fats, are they good or bad?!?!?

Fats of this type are still ‘good’ for you but what isn’t good is the over-consumption of specific nutrients. Too much water can kill you. The potential benefits show themselves in a ‘normal’ range of consumption the majority of the possible pitfalls coming to light when consumption increases. This change is usually due to a change in our dietary behaviour.

In a nut shell you’ll see the benefits of omega 6 written on the packaging of many foods, and you’ll be encouraged to eat more but you are very probably getting more that enough in your daily diet.

Don’t worry about this though your emphasis should again be on the foods not the nutrients, nutritional scientists don’t know what ‘optimum’ diet is of what all the nutrients so so there is no reason you should worry about it!

Address WHOLE diet, don’t focus in the nutrient in question

• Eat wholesome minimally processed foods
• Don’t over consuming grain based foods when you do make sure they are brown not white
• Include lots of fresh veg (aim for 10 servings a day – you’ll fall short but it’s better than aiming for 5 and falling short!)
• Regularly eat sources of omega 3 such as oily fish, walnuts, flax seed oils. At a push you might consider a supplement if the above down appear in your diet frequently.

Read the article at the BBC website HERE

Read the original research at GUT the internation journal of gastroenterology & hepatology HERE

UPDATE:

I’ve been asked to include a little detail on the above issues.

Ulcerative colitis

This is a type of inflammatory bowel disease, a form of colitis where the unfortunate sufferer develops sores on the lining of the gut. Symptoms include pain, diarrhea and blood on the faeces. The cause of UC is not well understood but it is probably a mutifactorial including environment, diet and a genetic predisposition, there may also be involvement of the gut flora in the development of the condition though this is disputed.

UC is diagnosed using a combination of blood tests and then endoscopy and possibly biopsies to examine the gut. Treatment includes medication for the condition and in more server cases surgery to remove the offending portions of bowel. UC is associated with other conditions possibly due to the suggested autoimmune component these co-morbidities can include arthritis and ankylosing spondylitis

What are essential fats ?

Fat or ‘fatty acid’ is actually a collective name for a whole range of structurally similar but chemically different compounds. You are probably already be familiar with saturated, mono-unsaturated and poly-unsaturated fats however these can be further sub-divided in many groups.

Saturated, mono-unsaturated and poly-unsaturated fats are all necessary for health, these groups have different fates and roles within the body. Many utilised by the body to make other kinds of fats though in case of some fats this cannot be carried out. These ‘essential fatty acids’ are ‘essential’ because the body is unable to manufacture then from other compounds.

How would omega 6 be linked with inflammation and ulcerative colitis?

Inflammation is a useful physiological process which is intrinsic in the repair process of damaged tissues involving both the circulatory and immune systems and it is regulated by a whole host of different signaling compounds. Inflammation can be chronic of acute. Chronic inflammation is an issue that is associated with may of the degenerative and ‘lifestyle’ health issues that we see today and has an immune component.

Your ‘inflammatory state’ can be modulated by a range of different factors, lifestyle, stress, disease and also diet. There is a clear mechanism involving nutrients that you eat and this is where the omega 3 and omega 6 fats come in.

These two polyunsaturated fats form the building blocks, the raw material, for the manufacture of the ‘eicosanoids’. These eicosanoids are short lived localised hormones produced by cells and are involved in the control of inflammation and immune system behaviour and come in different varieties broadly pro and anti inflammatory.

Eicosanoids produced from omega 6 fats are broadly inflammatory and those produced from omega 3 generally have an anti-inflammatory action.

Being that UC has both a immune and inflammation component to is then it can be clearly see that there may well be a connection from a mechanistic point of view. As Dr Anton Emmanual, medical director at Core cautiously puts it

“Nevertheless there is good biological plausibility of why linoleic acid can cause inflamation, and certainly Western diets are often excessive in this kind of fat. “