Conjugated Linoleic Acid (CLA): Usage, Health Benefits & Side Effects

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Better known as CLA, Conjugated Linoleic Acid is a common ingredient in weight loss supplements.

Conjugated Linoleic Acid can be a supplement on its own or coupled with other popular ingredients. Apart from weight loss, CLA proponents credit it with many other health benefits.

In this article, we look at whether conjugated linoleic acid actually aids in weight loss, its benefits and side effects.

What is Conjugated Linoleic Acid?

Conjugated linoleic acid is a type of fatty acid whose main source is ruminant animals. These include cows, goats, sheep, and game meat like buffalo or deer.

It is sourced from ruminant animals’ meat and dairy products like milk and cheese [1]. CLA also exists in trace amounts in non-ruminant animals like pigs, chicken, and turkeys.

Conjugated linoleic acid is rich in Omega 6. Although CLA is a fatty acid, it is a polyunsaturated natural trans fat that is good for the heart.

Conjugated linoleic acid is considered an anti-obesity agent believed to aid with weight loss, building muscle and endurance. It is a common ingredient in weight loss supplements either on its own or coupled with other ingredients.

The CLA present in supplements is however not sourced from animals. They are made industrially through thermal treatments and contain only 30% of geometrical and positional isomers of actual CLA [2].

How Does Conjugated Linoleic Acid Work?

Research into conjugated linoleic acid has been going on for 30 years and counting. Lab research on mice and pigs has proven that CLA has some influence on the deposition of adipose tissue.

The adipose tissue is where pockets of fats are stored in the body. The study of CLA conducted on animals showed that it reduces body fat by increasing the amount of enzymes and proteins that break down these fats.

CLA was also proven to inhibit fat gain in animals [3]. Increased CLA dosage inversely led to a decrease in body fat gained.

This phenomenon was observed in a study conducted among pigs.

In one study, a group of mice was fed CLA supplements and set up against a placebo group. In just six weeks, the mice that had taken CLA lost up to 70% body fat compared to the placebo group, which lost none.

Clinical trials were later on conducted to ascertain the anti-obesity properties of conjugated linoleic acid. The trials confirmed that indeed CLA helps reduce body fat in humans too but with very modest results

Because of its fat-burning properties, CLA is taken as supplements used alongside exercise by bodybuilders to build muscles.

Is Conjugated Linoleic Acid Safe?

Conjugated linoleic acid from food sources like beef and milk is definitely safe to consume. CLA supplements, however, are a different kettle of fish.

Supplements always have issues when it comes to safety guarantees because people react differently to different things. Much so with conjugated linoleic acid supplements because they are synthesized in the lab.

CLA supplements differ in composition from natural CLA present in ruminant animal products.

They are generally safe to take as long as one follows the prescription. Some people may experience a few symptoms synonymous with supplement intake.

These include a headache, tummy ache just mild discomfort here and there. The side effects more often than not ultimately pass.

Just to be safe, consult a doctor before taking any conjugated linoleic acid supplements. Also, call a doctor when side effects persist.

Later on, we will look at other safety issues that have been linked to CLA as well as some precautions.

Health Benefits of Conjugated Linoleic Acid

The proponents of conjugated linoleic acid consider it a functional food. Research into its health benefits has been ongoing for the last three decades.

Functional foods are those that do more for the body than meeting the classic nutritional needs.

Here are some of the health benefits that have been linked to conjugated linoleic acid.

  • Weight loss – this is the most popular CLA application. Conjugated linoleic acid affects adiposity through its involvement in fat metabolism
  • Heightened immune response as indicated by increased white blood cells
  • Modulating one’s glycemic profile hence reducing the risk of Type II diabetes. It improves insulin resistance [4,5].
  • Inhibiting the development of atherosclerosis- this condition indicated by the narrowing of the arteries. The narrowing of arteries results from fat deposition along the arterial walls [6].
  • Improved mineralization of the bones
  • Lowers risk of heart disease by reducing cholesterol

Some conjugated linoleic acid proponents even link it to cancer prevention, increased energy levels, and endurance.

All these health benefits make CLA seem like the key to health and wellness. The efficacy of conjugated linoleic acid, even in weight loss is still under research.

Also when it comes to weight loss, the supplements are often taken alongside either a strict diet, or exercise, or both. This implies the supplements are only part of the solution and not the ultimate cure.

The best option would be to consult your doctor prior to taking conjugated linoleic acid supplements for any purpose. This is way safer than self-medicating.

Conjugated Linoleic Acid Side Effects

CLA supplements are made by altering plant sources of CLA to mimic the chemical of actual Conjugated linoleic acid present in ruminant animal sources.  More often than not they are coupled with other ingredients like caffeine and guarana in supplement capsules.

Conjugated linoleic acid supplements are ranked by the FDA as generally safe to use. However, one may experience a few side effects here and there

Some of the short term side effects that have been linked to conjugated linoleic acid supplementation include:

  • Tummy upsets
  • Constipation
  • Fatigue
  • Headache
  • Backache
  • Indigestion

The side effects have been ranked between mild and moderate by conjugated linoleic acid supplements users. The symptoms should reduce gradually and ultimately stop, but in case of the contrary, consult your doctor.

Conjugated Linoleic Acid Usage and Dosing Considerations

Health Benefits of Conjugated Linoleic Acid

Although conjugated linoleic acid supplements are considered relatively safe for consumption, too much of CLA is bad. Some of the adverse health risks we will delve into later have been linked to CLA supplements overdose.

The research on CLA supplements is quite conflicting. But most case studies suggest taking between 3-6 milligrams per a day. Anything above that would not increase health benefits but rather would increase the risk of adverse health conditions [7, 8].

CLA supplements are available in capsule and syrup form. The dosage varies according to factors like supplement brand and matter state.

You might also want to consider the taste. While some CLA supplements are sweet, others are quite bitter and have an aftertaste.

Conjugated linoleic acid proponents suggest that the best time to take the supplements is before or during a meal. If you are taking them alongside an exercise regimen, then the best time is before a workout.

So yes, you can take CLA supplements on an empty stomach with no harm.

How many times in a day you take the supplements will, however, depend on the brand. The best way to take it, for instance, mixing it with your food, will also depend on the brand and prescription.

Conjugated linoleic supplements can be taken by both men and women seeking to lose weight. Regarding age, there is no consensus on the age limit for taking CLA supplements.

Given the insufficient research into long term use of CLA supplements, it is best not to give them to children. Most weight loss supplements have an age restriction of 18 years and over only.

Consult a doctor especially if you are a teenager seeking weight loss before doing anything rash.

As previously stated, there is insufficient research on long term use of CLA supplementation. Hence there is no consensus on the minimum duration to use CLA before achieving results.

That is something you should bear in mind.

Risks and Precautions

Some factions of researchers have linked conjugated linoleic acid supplements to serious health conditions. These include liver and kidney diseases [9, 10].

CLA supplements have also been linked to more adverse effects on general health. Some studies have linked the supplements with:

  • Increased levels of LDL and reduced HDL – LDL refers to harmful fats like cholesterol while HDL are good, healthy fats.
  • Insulin resistance, which may lead to hypoglycemia
  • Increase risk of systemic inflammation caused by increased levels of c-reactive protein in the body. Chronic inflammation can lead to heart disease [11, 12].
  • Liver toxicity and liver fatty disease.
  • Oxidative stress which if left unchecked could lead to cancer and heart disease
  • CLA may slow down the blood clotting process leading to easier bruising [13]
  • Irritation of the intestinal tract – one will experience bloating, flatulence, and indigestion

The adverse symptoms are extreme and rarely occur. However, bear in mind that research into the side effects of conjugated linoleic acid is as of yet inconclusive and insufficient.

There is also insufficient research on the long term effects of CLA supplementation. To be on the safe side consult a doctor prior to taking conjugated linoleic acid supplements.

To avoid these health crippling risks, there are a few precautions you can also follow.

  • Do not take conjugated linoleic acid supplements alongside blood thinners or anticoagulation medication
  • Do not take CLA supplements with anti-inflammatory drugs
  • Don’t take the supplements if you are a diabetic. Consult your doctor first.
  • Conjugated linoleic acid supplements should not be taken by pregnant or breastfeeding mothers
  • If you have liver or kidney disease, do not take CLA supplements. They could aggravate the situation.
  • Reveal your medical history to your doctor and get some sound advice prior to taking CLA supplements
  • Do not give CLA supplements to children without consulting a doctor first.
  • Take the supplements as instructed by your doctor or on the package. Remember, anything more than 6g can lead to organ damage
  • Check the ingredients as listed on the supplements’ packaging especially if you are prone to allergies.

The above risks are linked to synthetic conjugated linoleic acid found in supplements. If your source of CLA is meat and dairy, you don’t have to lose a wink sleepover side effects.

Not to scare you if you would rather take CLA supplements. Remember, the health risks are synonymous with overdosing and are rare cases.

Follow your prescription as instructed and you’ll have nothing to fear.


Can I take conjugated linoleic acid every day?

The duration over which you take conjugated linoleic acid will be determined by either the prescription or the instructions on the supplement package.

Can I take conjugated linoleic acid on an empty stomach?

Yes, it is recommended to take CLA supplements either before or alongside your meal

What is the best time to take conjugated linoleic acid?

There is no consensus on the best time of day to take CLA for maximum results, just follow the instructions on your prescription.

Is taking conjugated linoleic acid supplements good for your skin?

At the moment, there is no research linking the consumption of CLA supplements to a healthier skin

Can conjugated linoleic acid hurt your kidneys?

Some research studies have shown that taking more than the recommended 6g of CLA supplements per day can over time lead to kidney disease.

Is conjugated linoleic acid good for arthritis

At the moment there is no research suggesting that CLA may have any effect on arthritis


Conjugated linoleic acid has been painted by its proponents as a quick fix for quite a number of health issues. Like with anything else on the internet, take the hype with a dose of skepticism.

Although CLA is viewed as a functional food, it is really non-essential. That means our bodies can pretty much do without it.

Food sources of CLA are safer than supplements. If you have to take CLA, consider drinking more milk, it is way friendlier to your body.

If you are vegan some mushrooms are rare plan sources of conjugated linoleic acid. You can try these.

The hype around conjugated linoleic acid is focused on its weight loss properties. However, the astounding weight loss results posted by mice in the lab were not replicated by human subjects in clinical trials.

The actual weight loss from CLA is very modest, yet the supplements are linked to a lot of serious side effects. Inadequate research into long term use is another worrying factor.

When it comes to weight loss exercise and healthy diets like keto are much better options. Weight loss is not just about shedding fat, it involves a complete lifestyle overhaul and commitment.

With exercise and diet, results may be slow but definitely worth it.




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