Do omega-3 supplements really work? – 01/10/2023 – Balance

It is often advertised that fish oil – which contains omega-3 fatty acids – brings a series of benefits, ranging from promoting our health, protecting the brain against dementia and reducing the symptoms of rheumatoid arthritis.

But what exactly are omega-3 fats and what does the evidence say about their benefits for maintaining our health?

And if they really are good for us, does eating fish provide the same benefits as supplements?

What is omega-3?

Omega-3 fatty acids are a type of polyunsaturated fatty acid. Their consumption in our diet is essential, as our body cannot manufacture them.

Three main types of omega-3 are important in our diet:

• Alpha-linolenic acid (ALA), found in plant foods such as green leafy vegetables, walnuts, and flax and chia seeds;
• Eicosapentaenoic acid (EPA), found only in foods of marine origin, eggs (its level is higher in eggs from free-range birds than in cages) and breast milk;
• Docosahexaenoic acid (DHA), also found only in fish and seafood, eggs (again, highest in free-range poultry eggs) and breast milk.

Omega-3 fatty acids are fundamental to the structure of our cells and help keep our heart, lungs, blood vessels and immune system functioning.

Eating fish vs taking supplements

The initial studies that indicated that omega-3 fats may have health benefits came from observational studies of people who ate fish, not fish oil.

But does our body absorb the “active ingredients” from supplements – EPA and DHA – in the same way as from fish?

An intervention study (in which one group receives fish and the other receives fish oil supplements) concluded that levels of EPA and DHA in the body increase similarly when we consume equal amounts of fish or fish oil.

But here we consider that only omega-3 would provide health benefits. There are other components of fish, such as proteins, vitamins A and D, iodine and selenium, which may be responsible for the health benefits, together or separately.

And the observed benefits may also be due, in part, to the absence of certain nutrients from other types of meat (red and processed) that would have been consumed instead of fish, such as salt and saturated fats.

So what are the benefits? And does the font make a difference?

Let’s consider the evidence regarding heart disease, arthritis, and dementia.

Heart diseases

Regarding cardiovascular diseases such as heart attacks and strokes, a meta-analysis (which provides the highest quality evidence) demonstrated that fish oil supplementation probably makes little or no difference.

Another meta-analysis concluded that every 20 grams of fish daily reduced the risk of coronary heart disease by 4%.

Based on scientific evidence, the National Heart Foundation of Australia recommends consuming fish rich in omega-3 to improve heart health.

The level of omega-3 varies between fish species. In general, the greater the fish flavor, the higher the omega-3 levels – such as tuna, salmon, orange roughy, jack, mackerel and sea bass.

The Australian foundation says fish oil may be beneficial for people with heart failure or high triglycerides, which are a type of fat that circulates in the blood and increases the risk of heart disease and stroke. But she does not recommend consuming fish oil to reduce the risk of cardiovascular disease (heart attack and stroke).

Arthritis

For rheumatoid arthritis, studies have shown that fish oil supplements actually provide benefits in reducing the severity and progression of the disease.

Consuming fish also brings these improvements, but as the required level of EPA and DHA is high, it is often expensive and difficult to consume this amount from fish alone.

Based on evidence, the organization Arthritis Australia recommends about 2.7 grams of EPA and DHA per day to reduce joint inflammation. Most supplements contain around 300-400 mg of omega-3s.

So, depending on how much EPA and DHA is in each capsule, you may need 9 to 14 capsules (or 5 to 7 capsules of fish oil concentrate) per day. This amount is equivalent to around 130-140 g of grilled salmon or mackerel, or 350 g of canned tuna in brine (almost four small cans).

Insanity

Epidemiological studies have shown that there is a positive relationship between increasing DHA intake (from food) and reducing the risk of developing Alzheimer’s, which is a type of dementia.

Animal studies have concluded that DHA may alter markers used to assess brain function (such as the accumulation of amyloid, a protein believed to be linked to dementia, and changes in the protein tau, which helps stabilize nerve cells in the brain). . But this effect has not yet been demonstrated in humans.

A systematic analysis of several human studies demonstrated different results for supplement-derived omega-3 fatty acids.

In the two studies that offered omega-3 in supplement form to people with dementia, there were no improvements. But when given to people with mild cognitive impairment (a condition associated with increased risk of progression to dementia), benefits were found.

Another meta-analysis demonstrated that higher fish intake is related to a lower risk of Alzheimer’s. But this relationship was not observed with total dietary intake of omega-3. This indicates that there may be other protective benefits derived from fish consumption.

Considering the evidence, the British Alzheimer’s Society recommends consuming fish and not taking fish oil supplements.

What to conclude, then?

The more people adopt a healthy, plant-based diet, including fish and with minimal intake of ultra-processed foods, the better their health will be.

Currently, evidence indicates that fish oil is beneficial for rheumatoid arthritis, particularly if people have difficulty consuming large amounts of fish.

For dementia and heart disease, it’s best to try to get omega-3s from your diet. Plant foods contain ALA, but it will be more efficient to increase EPA and DHA levels in the body by consuming marine foods.

Like any product available on store shelves, check the expiration date on fish oil and make sure you can consume it on time. The chemical structure of EPA and DHA makes the product susceptible to degradation, which impairs its nutritional value.

Store the supplement in a cold environment, preferably in the refrigerator, away from light.

Fish oil can have unpleasant side effects, such as fishy-smelling burps, but serious side effects are generally minimal.

Still, it’s important to discuss fish oil consumption with all your doctors, especially if you take other medications.

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This article was originally published on the academic news website The Conversation and is republished under a Creative Commons license. Read the original English version here.

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