Eating for a Healthy Brain
Certain food constituents are widely believed to improve brain function and protect against the negative effects of ageing. These include omega-3 polyunsaturated fatty acids (PUFAs), antioxidants, folic acid and vitamin E complex. Many foods rich in these substances are promoted as "brain foods" and are often subject to wide-ranging health claims. Let us examine some of the most common brain foods.
Fish
Fish and seafood are well-known sources of PUFAs and other brain-protecting constituents. As well as being rich in many important nutrients, fish is considered one of the healthiest foods for the brain. It is increasingly common for people to take fish oil supplements daily to improve brain function. However, fish is also the primary source of methyl-mercury (MeHg) in most diets, a compound that can have detrimental effects if consumed in high doses. The risk is particularly concerning for pregnant women, as high intake of MeHg has been associated with brain developmental problems in uterus. Some studies have shown that children, whose mothers consumed large amounts of fish high in MeHg during pregnancy, perform worse on IQ tests and have difficulty with language and gross-motor skills. This appears to outweigh the benefits of PUFAs in fish and suggests a dietary balance needs to be found.
2011 report published in the journal Nutrition Reviews summarised the evidence around the issue and made dietary recommendations accordingly. It noted that the concentration of PUFAs and MeHg varies between species of fish, sometimes dramatically. Predatory fish generally absorb higher levels of MeHg, with species such as shark, swordfish and large blue-fin tuna among those with the highest concentration. However, popular eating fish such as mackerel, salmon and sardines all contain high levels of PUFAs with only small to moderate amounts of MeHg, giving consumers the health benefits of fish without the risks. Food Standards Australia New Zealand (FSANZ) recommends the general population eat two to three serves of fish or seafood per week, with a slight reduction for children and pregnant women. Some high MeHg fish such as shark, swordfish and merlin should only be eaten once a week.
The Nutrition Reviews report noted that replacements such as fish oil and eggs can also provide adequate PUFAs for those who cannot or choose not to eat fish.
Fish
Fish and seafood are well-known sources of PUFAs and other brain-protecting constituents. As well as being rich in many important nutrients, fish is considered one of the healthiest foods for the brain. It is increasingly common for people to take fish oil supplements daily to improve brain function. However, fish is also the primary source of methyl-mercury (MeHg) in most diets, a compound that can have detrimental effects if consumed in high doses. The risk is particularly concerning for pregnant women, as high intake of MeHg has been associated with brain developmental problems in uterus. Some studies have shown that children, whose mothers consumed large amounts of fish high in MeHg during pregnancy, perform worse on IQ tests and have difficulty with language and gross-motor skills. This appears to outweigh the benefits of PUFAs in fish and suggests a dietary balance needs to be found.
2011 report published in the journal Nutrition Reviews summarised the evidence around the issue and made dietary recommendations accordingly. It noted that the concentration of PUFAs and MeHg varies between species of fish, sometimes dramatically. Predatory fish generally absorb higher levels of MeHg, with species such as shark, swordfish and large blue-fin tuna among those with the highest concentration. However, popular eating fish such as mackerel, salmon and sardines all contain high levels of PUFAs with only small to moderate amounts of MeHg, giving consumers the health benefits of fish without the risks. Food Standards Australia New Zealand (FSANZ) recommends the general population eat two to three serves of fish or seafood per week, with a slight reduction for children and pregnant women. Some high MeHg fish such as shark, swordfish and merlin should only be eaten once a week.
The Nutrition Reviews report noted that replacements such as fish oil and eggs can also provide adequate PUFAs for those who cannot or choose not to eat fish.