Introduction to CLA
Fats come in various types. Some are merely for energy – supply, while others have a significant impact on health. Conjugated linoleic acid (CLA) is a fatty acid present in meat and dairy products, believed to offer multiple health benefits and is a well – known weight loss supplement. This article delves into the effects of CLA on fat loss and overall health.
What Exactly is CLA?
Linoleic acid is the most common omega – 6 fatty acid, abundant in vegetable oils and present in trace amounts in other foods. The term “conjugation” pertains to the arrangement of double bonds in the fatty acid molecule. There are 28 different forms of CLA, which vary in the configuration of their double bonds. Despite its minuscule nature, this can have a profound impact on our cells. CLA is a polyunsaturated omega – 6 fatty acid. Technically, it is a trans fat, but a natural one found in many healthy foods. It should be noted that industrial production of trans fats is very different from natural trans fats like CLA; artificially – produced trans fats are harmful when consumed in large quantities.
The main dietary sources of CLA are the meat and milk of ruminants such as cattle and sheep. The amount of conjugated linoleic acid in these foods can vary greatly depending on the animal’s diet. For instance, grass – fed cattle have 300 – 500% more CLA in their beef and dairy products than grain – fed cattle. Most people already consume some CLA through their diet. In the US, the average daily intake for women is about 151 mg and 212 mg for men. However, much of the CLA in nutritional products is not from natural foods but from a chemical change in linoleic acid in vegetable oils, which may not provide the same health benefits as natural food – sourced CLA.
CLA and Fat Loss
The biological activity of CLA was first noticed when researchers found it could help fight cancer in rats. Later, it was thought to reduce body fat levels. With the global rise in obesity, CLA has been considered a potential weight loss solution. CLA is one of the most well – studied weight loss nutrients globally. Animal studies have shown that it can reduce body fat in multiple ways. In mouse studies, it was found to decrease food intake, boost fat burning, stimulate lipolysis, and inhibit lipogenesis.
Randomised controlled trials in humans, the gold standard of scientific trials, have also been conducted on CLA, but the results are inconsistent. Some studies suggest that CLA can lead to significant fat loss in humans and improve body composition by reducing fat and increasing muscle mass. However, many studies show no effect. A controlled trial of 18 studies found that CLA could moderately reduce fat, with the most significant effect in the first six months after weight loss, followed by a plateau over the next two years. Overall, it is more effective than some similar supplements for weight loss, yet its effects are small, uncertain, and may not impact daily life significantly.
Potential Health Benefits of CLA
In nature, CLA is mainly found in fatty meat and dairy products from ruminants. Many long – term observational studies have evaluated the disease risk in populations with high CLA intake. Notably, those who get a high amount of CLA from their diet have a lower risk of diseases like type 2 diabetes and cancer. In countries where cows mainly eat grass, studies have shown that people with high levels of CLA in their bodies have a lower risk of heart disease. However, this could also be due to other protective components in grass – fed animal products, such as vitamin K2.
Side Effects of High – Dose CLA
There is evidence that small amounts of natural CLA from food can be beneficial. However, many CLA supplements are made by chemically altering linoleic acid in vegetable oils and are in a different form from natural food – sourced CLA. Supplement doses are also much higher than those from dairy products or meat. In general, some molecules and nutrients that are beneficial in natural food amounts can be harmful in large amounts, and CLA supplements are no exception.
High doses of CLA can lead to liver fat accumulation, a precursor to metabolic syndrome and diabetes. Numerous animal and human studies have shown that it can cause inflammation, insulin resistance, and lower “good” HDL cholesterol. Although many animal studies used doses much higher than human supplement doses, some human studies with reasonable doses have shown that CLA supplementation may cause mild or moderate side effects like diarrhoea, insulin resistance, and oxidative stress.
Dosage and Safety Considerations
Most CLA studies have used doses of 3.2 – 6.4 g per day. A review suggested that at least 3 grams per day is needed for weight loss, and doses up to 6 grams per day are considered safe with no serious adverse side effects reported. However, the risk of side effects increases with the dose. Given that CLA has a limited effect on weight loss and there are concerns about the long – term health effects of supplement doses, it is advisable to consume CLA from natural foods as much as possible if not specifically required.
