We’ve been guilty of polluting the environment with plastic for a long time and there’s an ever-increasing amount of data showing the extent of the problem. A very recent study assessed the presence of plastic debris in fish and shellfish on sale for human consumption in Indonesia and California.
In Indonesia, plastic was found in 28 per cent of individual fish and in 55 per cent of all species. The majority was plastic fragments but also considerable amount of plastic foam was found, accompanied by plastic film and plastic monofilament line.
The journal Environmental Research published a study investigating the effects of fish consumption on children’s health. It confirmed that regular fish intake is responsible for increased levels of mercury in the blood. Even though the levels of fish-consuming children were below the potential risk level, researchers found that they had disrupted hormone (adrenocortical) function that may result in the development of physical and psychological disorders.
Dr Justine Butler explains why fish oils are not the best choice
Like a record stuck in a groove – the advice just keeps on repeating itself.
Dangerous environmental pollutants called polychlorinated biphenyls (PCBs) were the first industrial compounds to experience a worldwide ban on production more than 30 years ago because of their potent toxicity. However, they are very persistent and therefore still present in our environment. Once in the body, PCBs accumulate in the fat tissue and can cause long-term problems such as reduced infection fighting ability, mental and behavioural problems, decreased activity of the thyroid, reproductive problems, can induce cancer and severely damage the development of a baby.
Do we need fish oils for health or have we been sold down the line? In a new scientific report, the VVF has examined the health claims for fish and unearthed the research that the fish industry would rather ignore.
EVERYWHERE YOU LOOK THESE DAYS FISH OILS ARE being promoted – celebrity scientists recommend them to children, TV adverts imply brain-boosting benefits, food producers slip them into all manner of foods!
A recent study published in the American Journal of Clinical Nutrition showed that vegan women have significantly more omega-3 fats (the good fats we are constantly being told to eat) in their blood than fish-eaters, meat-eaters, and lacto-ovo vegetarians. Vegan men had slightly lower levels than vegan women but the same pattern was observed in the other groups as well and was thought to be linked to female hormones influencing the metabolism to a certain extent. An astonishing 14,422 men and women aged 39 to 78 participated in this study.
Eating fish is often promoted as beneficial to heart health. New research from the Rotterdam Study looking at fish intake and the incidence of heart failure found that fish did not offer such protection. Researchers followed the diets of over 5,000 adults for 11 years during which time almost 670 had heart attacks. Results showed that eating fish made no difference to the risk of heart failure.
A new study from Harvard links fish and omega-3 oils to type 2 diabetes. Following almost 200,000 adults for up to 18 years, researchers found that the more fish or long chain omega-3 fatty acids participants consumed, the higher their risk of developing diabetes. Those who ate fish occasionally had a modest increase in risk, but those eating fish five or more times per week had a 22 per cent increase. Prior studies have suggested that fat building up in muscle cells can lead to insulin resistance which, in turn, contributes to diabetes.
Researchers in Canada say that the supposed health benefits of eating fish are over-stated and are putting pressure on wild fish. Fish oils are promoted for heart health, but results are mixed. Vegetarians don’t have an increased risk of heart disease (in fact, they have a 25 per cent lower risk). Safer, healthier sources of omega-3s include flaxseed oil and algal supplements. Farley Mowat, co-author of the study, said: “The damage we have already done to life in the oceans is a prime example of our idiocy, and a last warning that we had better change our ways”.
A landmark study from Harvard University predicts mercury levels in the Pacific Ocean will rise 50 per cent by 2050 if emission rates continue as expected. Mercury rapidly accumulates up the food chain in the sea to potentially dangerous levels in larger fish such as tuna. Previous studies show that 75 per cent of the mercury people are exposed to comes from eating marine fish and shell fish.
One of the arguments used to promote oily fish is that it provides the long chain omega-3 fats EPA and DHA important for health. Omega-3 from plants (ALA) is converted in the body to EPA and DHA but conversion rates may be low. However, new research indicates that vegetarians convert ALA at a better rate than fish-eaters. This may explain why fish-eaters and non fish-eaters have a smaller than expected difference in omega-3 levels.
Further evidence linking pollutants to type 2 diabetes has emerged. The new research published in Diabetes Care shows that people with high levels of persistent organic pollutants (POPs) in the blood are 38 times more likely to have some degree of insulin-resistance – a precursor to diabetes. Although obesity is a well-documented risk factor for diabetes, this study suggests that obese people with low levels of POPs have an unexpectedly low incidence of diabetes and that obesity is only associated with diabetes in those with high levels of POPs.
New research from the Harvard School of Public Health shows that eating oily fish during pregnancy could raise the risk of premature birth. The blame may lie with the high levels of mercury found in some fish. In this research, information was gathered from 1,024 pregnant women on the amount and type of fish eaten during the pregnancy. Hair samples were taken and the amount of mercury in each sample was measured. Results showed that those who ate the most fish, (especially canned fish), had the highest levels of mercury. And women who gave birth more than two w
In the last issue of Veggiehealth we explained why fish oils are not the best source of omega-3 fats. A major new study published in the British Medical Journal supports this view. The team, led by Dr Lee Hooper of the University of East Anglia, found little evidence that eating fish or taking fish oil capsules, cuts the risk of dying of heart disease, stroke or cancer. This review suggests that pollutants in fish (mercury, dioxins and polychlorinated biphenyls), may cancel out the beneficial effects of the ‘good’ omega-3 fats they contain.