Some supplements can be helpful, but many are dangerous if you take too much. Conjugated linoleic acid, also known as CLA, is no different. Taking the proper CLA dosage will give you the maximum benefit, without harmful side effects.
Conjugated Linoleic Acid Background
Conjugated linoleic acid is a supplement commonly found in animal meat and dairy products. It's derived from linoleic acid, which is an essential fatty acid. The body can't make it's own fatty acids, so you have to get them through diet.
One of the biggest sources of CLA is milk, which has a few known health benefits. Drinking milk can help you build and maintain strong bones. It can also help with Type 2 diabetes, and may prevent certain types of cancer.
While the calcium and vitamin D in milk help with bone health, it's not yet known what helps prevent cancer. CLA is being investigated as a potential cause of the other health benefits found when consuming milk.
Like any supplement, you need to know if it works, how much to take and whether or not it's safe. According to a research review on conjugated linoleic acid, published in the Journal of the International Society of Sports Nutrition in September 2015, results are inconclusive.
In the research review, scientists looked at a host of studies on humans and animals. They found that some studies showed benefits, while others showed negative side effects, like higher blood lipids and blood glucose.
CLA Benefits and Dangers
The biggest benefits currently being researched are found in body composition. There's some evidence that taking conjugated linoleic acid can reduce your body fat. However, more studies are needed.
Another study, published in May 2017 in Critical Reviews in Food Science and Nutrition, agrees that the current research on conjugated linoleic acid is inconclusive. In this research review, the scientists conclude that CLA most likely can help with body composition. They mention that recent studies show some benefit in humans.
At the same time, there doesn't seem to be much benefit for health. There isn't much evidence that CLA helps prevent cardiovascular disease, decrease inflammation or controls blood glucose. While there may be some benefit accrued from taking CLA, research so far is mixed.
There's no one single dosage recommendation for CLA. Some studies use a moderate amount, while others try to push the limit and use large doses. Some studies use different doses to try to affect different areas of health.
A February 2015 study published in Nutrition and Metabolism shows the dosage protocol for multiple CLA studies in humans. There's a variety of studies for body composition and health. Some of the studies used a CLA dosage as low as 0.7 grams per day for their smallest dose, and some use up to 8 grams per day. This wide a range leaves much room for interpretation.
It should be noted that out of all the studies cited in the research review, many had doses between 3 and 4 grams. In fact, that was one of the most common ranges, so you should start somewhere in that range if you're interested in taking CLA experimentally.
Read more: CLA for Weight Loss and When to Take It
CLA Side Effects
On one hand, your dose needs to be high enough to have a measurable effect on your body. On the other hand, it shouldn't be so high that you experience side effects. The most well-known side effects are fatigue and gastrointestinal problems.
You shouldn't take CLA if you're on a blood thinning drug, as your blood can become too thin. If you have diabetes, you should avoid CLA because it can increase blood sugar. In people with heart problems, CLA can increase cellular damage, which is dangerous.
While there's no set upper-limit for CLA, dosages of up to 8 grams has been used in research without significant side effects. However, beyond that there's very little research. Additionally, long-term research at high doses is lacking. Until more research is completed on the toxicity of CLA, stick to moderate doses and check with your doctor before taking any supplements.
- Memorial Sloane Kettering Cancer Center: "Conjugated Linoleic Acid"
- Nutrition & Metabolism: "Pros and Cons of CLA Consumption: An Insight From Clinical Evidences"
- Critical Reviews in Food Science and Nutrition: "Conjugated Linoleic Acid: A Potent Fatty Acid Linked to Animal and Human Health"
- Journal of the International Society of Sports Nutrition: "A Review on Effects of Conjugated Linoleic Fatty Acid (CLA) Upon Body Composition and Energetic Metabolism"
- Food & Nutrition Research: "Milk and Dairy Products: Good or Bad for Human Health? An Assessment of the Totality of Scientific Evidence"