A CLA Supplement Primer
Fitness and body building blogs are awash with information lauding CLA supplements as a fat blocking supplement. Losing fat with fat seems to be yet another dubious dieting promise and there may be more truth to the claims than many other dieting infomercials.
But apart from cosmetic effects like weight loss and body shape, there are claims that CLA supplements can also treat a variety of illnesses including cancer. In this article, we will take a look at some of these claims and see if there is any substance to them.
What is CLA?
CLA stands for conjugated linoleic acid which is a fatty acid related to omega-6; one of the fatty acids which help boost metabolism and immunity as well as keeping cholesterol levels in control. CLA is naturally found in certain animal fats like beef and lamb as well as dairy products and eggs though it cannot be produced in the body.
While the trend towards these supplements is new, interest in CLA actually dates back to the 1980s when professor Pariza of the University of Wisconsin discovered that an isolated compound found in a fried hamburger decreases the incidence of cancer in rodents.
It wasn’t until a few years after this discovery that the research team identified the agent as a type of linoleic acid which they named conjugated lionelic acid (CLA)
The benefits of CLA supplements
Weight loss and CLA
Now that the compound was isolated, there was great interest from the scientific community who set out to examine its effects. While some of the studies were contradictory, the consistent finding was that CLA helped people to shed body fat.
One of the best-known studies was a Norwegian one published in the year 2000 in the Journal of Nutrition. The researchers discovered that CLA helped decrease body fat and also preserved muscle in obese and overweight subjects even when they did not alter their diets.
Indeed over a 12 week period, those who took the supplements lost an average of 6 pounds of body fat compared with the 30 people in the control group. The CLA groupalso reported an improvement in quality of life at the end of the experiment.(1)
A number of studies have followed many of which show that CLA is an effective weight loss supplement for both overweight people and for the reduction of body fat percentage in those of a normal weight.
How does CLA work for weight loss?
According to experts in the field, CLA works by increasing metabolic rates; that basically means it helps your body convert food into energy more efficiently. It does not reduce overall body weight as such; instead it prevents fat cells from getting bigger which in turn alters the fat-muscle ratio in the body.
Studies have also showed that those who eventually stopped dieting as well as stopping the CLA supplements put weight back on in the expected manner at a ratio of 75% fat to 25% muscle. On the other hand, those who stopped their diet but continued taking CLA still gained weight but at a healthier 50/50 ratio of fat to muscle.
Other Benefits of CLA
While most of the articles and blogs surrounding CLA supplements focus heavily on their weight loss and fat busting benefits, there may be much more to gain from taking them. There is some fledgling evidence that CLA may increase muscular strength and endurance for athletes.
Other studies have examined their potential to reduce the incidence of certain cancers including breast, colon and prostate cancer. And that is not all, CLA supplements may also help boost your immune system, reduce cardiovascular disease and diabetes as well as treating degenerative bone diseases like osteoporosis.
- CLA and cancer preventionThe majority of research into the cancer preventing abilities of CLA has thus far been done in vitro or on animals but there has been some promising recent research on humans.In one of the earliest published studies from 1991, researchers at Buffalo’s Roswell Park Cancer Institute discovered that CLA inhibited the progress of breast tumors in rodents.The research team concluded that CLA was potent than other fatty acids when it came to preventing the development of tumors. (2)
Another animal study published in 1998 injected prostate cancer cells from humans into mice and found that the mice given CLA supplementation developed significantly smaller tumors. As well as that, the likelihood of the cancer spreading into the lungs was reduced. Researchers concluded that CLA supplementation was a potential future treatment for prostate cancer. (3)A very recent Iranian study published in 2013 examined the effect of CLA on inflammation in those receiving chemotherapy to treat rectal cancer.
They found evidence that CLA could improve the level of proteins linked to inflammation and inhibit the growth of blood vessels responsible for sustaining tumors and their growth. The researchers concluded in optimistic manner by suggesting CLA was a potentially effective complementary treatment for rectal cancer. (4)
- Cardiovascular disease preventionThe incidence of heart disease is on the rise especially in the Western world so it is extremely important that we find a way to reverse the trend. Fortunately, it appears that CLA supplements may be able to help.Due to the fact that CLA regulates the fat stored in the body as energy, it might prevent and even treat various kinds of heart disease including atherosclerosis.Experts at the Pennington Research Center suggest that CLA prevents lipids and plaques from being deposited in the arteries which is one of the key factors in the development and progress of heart diseases.CLA might also be able to protect against heart disease because of its antioxidant abilities and its potential to reduce blood pressure.
- Osteoporosis and CLAA variety of studies demonstrate that CLA supplements can help improve and retain bone density giving it potential applications for bone diseases like osteoporosis. According to research it may also have applications for rheumatoid arthritis and periodontitis. (5) (6)
How to take CLA
You can either try to increase your CLA intake naturally or get it from one of the growing range of CLA supplements available these days on the market.
The majority of studies have concluded that you should take 3.4 grams of CLA daily in order to see the benefits although the majority of these studies actually used far higher doses.
Natural Sources of CLA
If you would prefer to try increasing your CLA intake naturally, the best way to do this is by eating the beef of grass fed cattle. Of course, too much red meat is not necessarily a good thing and many people simply do not like red meat in which case a supplement may be the best and easiest option.
When it comes to milk which is another natural source of CLA, the quality of milk available might mean that your daily intake falls well short of the recommended dose. This is because of the changes in cattle feeding practice over the past few decades. So unless the cows have been pasture fed rather than the more commonly hay and silage fed cattle, drinking milk will not be enough.
As well as cows, other sources of natural CLA are sheep and goats provided they are grass fed. The CLA content that you get from grass-fed animals is between 300 and 500% higher when compared to animals which were grain-fed.
Provided you are not vegan or vegetarian, the likelihood is that you are already getting at least some CLA from your ordinary diet. According to research, the average daily intake of CLA in the United States is around 150 mg a day for women and 210 mg for men.
If you are going down the supplementary route then it is important to realize that the CLA you get in your supplements are not derived from natural sources. They are made through a chemical process which alters the composition of vegetable oils like sunflower and safflower oil which are not especially healthy in the first place. The chemical process involves converting the linoleic acid present in the vegetable oil into conjugated linoleic acid so basically that is what you are getting.
The bottom line here is that CLA obtained through supplementary means is nowhere near as healthy or as effective as the CLA you would be getting by consuming it naturally. Try getting your dose of CLA through natural means if it is at all possible. Of course, vegans and vegetarians may have no option other than to go down the supplementary route but please not that there are potential adverse side effects that I will look at later in the article.
CLA Side Effects
While CLA supplements are considered to be generally safe and non-toxic, you should consult a doctor before using them for the first time. This is especially important if you are a nursing mother or pregnant woman or if you have any pre-existing sicknesses.
There is plenty of evidence that when taken naturally in food that CLA is beneficial however, CLA taken in supplementary form may not be quite as beneficial mainly because it is produced by altering linoleic acid chemically from less than healthy vegetable oils. It is often true that nutrients which prove beneficial in real food and in normal amounts can become harmful when they are taken in large doses and some studies suggest that this is the case with regard to CLA supplements.
Several studies have actually indicated that when taken in large doses, CLA supplements can increase the amount of fat accumulated in the liver. This is problematic for several reasons and mat actually lead to metabolic syndrome and even diabetes.
Other studies done on both humans and animals show that despite their ability to reduce body fat percentages, CLA supplements can potentially increase inflammation, lower HDL cholesterol levels (the good type of cholesterol) and even lead to insulin resistance. Having said that, the animal studies in question used extremely high doses of CLA well above those that people generally use.
Even so, moderate doses of CLA supplements have caused several nasty side effects including diarrhea, nausea, flatulence and stomach pain.
Should you take CLA supplements?
So long as you are eating a healthy and balanced diet with plenty of meat then it seems unlikely that you would need to take CLA supplements. Since many people do not get enough it is probably worth taking as long as you cycle it in a 1-month on/off manner.