09 Dec How Effective are Omega-3s for Heart Health?
If you’ve read our recent blog on omega-3s, you’ll know that these long-chain fatty acids are essential for providing energy and regulating many different bodily functions. Our body doesn’t make them, so we need either to eat foods rich in omega-3s or supplement with them.
A big question that has arisen is: how effective is supplementing with Omega-3s in improving heart health and reducing the incidence of cardiovascular disease? There is plenty of research going into this subject at present and the results coming out of these studies are a mixed bag.
The benefits of omega-3s
What we do know is that fatty acids seem to contribute towards a healthy heart as they:
- Help to preserve the fluidity of cell membranes. This allows important molecules, such as phospholipids, to easily pass through them and results in quick repair of any damage to the membranes
- Improve communication across membranes, so that signals between cells are clearly sent and received, and the correct responses are triggered in the body
- Lower blood pressure, reducing any strain on the heart that can affect the efficient functioning of the heart muscle
- Decrease blood clotting, lowering the risk of a heart attack or stroke
- Reduce triglyceride levels (or fat in the bloodstream), which is then stored in fat cells for later use as energy, unless it is not used and therefore accumulates
- Slow the build-up of plaque and therefore lower the chances of developing a hardening of the arteries
- Balance the way in which sodium and calcium membrane channels operate, reducing the risk of arrhythmia
- Combat the effects of inflammatory omega-6s in multiple ways, reducing the risk of damage to vascular tissues, as well as the risk of other diseases caused by inflammation
A study at the Stanford University School of Medicine in California conducted a meta-analysis of 19 studies across 16 countries, including over 45,000 people without prevalent heart conditions. It found that increases in the levels of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA) together lowered the risk of fatal coronary heart disease by 11%.
This backs up the results of some studies elsewhere and contradicts those of others.
Other meta-analyses have been conducted by various bodies, including the U.S. Department of Health and Human Services and the Harvard T.H. Chan School of Public Health. These looked at studies across both healthy people and those who had already suffered from some form of heart disease.
All of them concluded that the evidence is, at best, weak that omega-3 supplementation helps to reduce the risk of stroke, myocardial infarction and cardiovascular death, as well as death from all causes.
There is some evidence that too much omega-3 may reduce the effectiveness of the immune system. This can create gastrointestinal problems such as indigestion or diarrhoea, and contribute to prostate cancer.
It can also result in a tendency to bleed due to its blood thinning and anti-clotting effects. Therefore it is not suitable for people taking certain medication, such as aspirin or warfarin, amongst many others.
Omega-3 is found in:
- Fish (especially wild farmed), particularly tuna, sardines, salmon, trout, mackerel and herring
- Flaxseeds and flaxseed oil
- Chia seeds
- Soy products
So people who are consuming fairly large quantities of these foods may already be getting enough omega-3. They should therefore be wary of adding more to their diet.
Risks of marine omega-3s
Added to this, as most omega-3s are derived from fish, it’s worth bearing in mind that:
- Fish spoils, and therefore fish oil can too, especially if it’s low quality and not processed and stored correctly. Be especially vigilant at keeping an eye on the expiration dates of the products on your shelves.
- Larger ocean fish often contain potentially harmful levels of mercury, and women who are pregnant or breastfeeding may want to either consider avoiding omega-3s, or making sure they only take high quality supplements.
- Anyone who cannot tolerate fish may suffer an allergic reaction such as skin rashes or difficulty with breathing.
In your store, before advising customers to add omega-3s to their supplement routine, check with them on their personal circumstances. If there is any doubt, refer them to a doctor first.
So while it seems likely that omega-3s may improve heart health and reduce the risk of cardiovascular disease, especially in people who already suffer from heart disease and perhaps in healthy individuals too, the jury is still out. More and better research is clearly required before we have a final verdict.