What fish oil can do for the brain

 

Omega-3 oils can help to boost your brain power as well as helping to stave off potential heart disease, writes JOANNE HUNT

THERE’S AN OIL crisis in Ireland, but for Limerick-born Dr Frank Ryan it’s not parched petrol pumps that are the worry. The co-author of the 1990 book The Eskimo Diet, which highlighted the importance of fish oils in our diet, points out that Irish people aren’t getting enough.

His book, based on research published in The Lancet, explains that fish oil lowers blood fat levels and dramatically reduces the risk of a heart attack.

What’s more controversial now, he says, is whether it can make us smarter and reduce our risk of Alzheimer’s disease. Ryan thinks it can.

A consultant physician to Sheffield teaching hospitals and a fellow of the Royal College of Medicine, Ryan has done his time on hospital wards. Seeing thousands of people with heart attacks, strokes and dementia turned him into a crusader for using changes in the diet to change lives.

Ryan has written The Brain Food Diet on the power of omega-3s to improve mental function. It’s no wonder he’s garnered fans in the fish processing and fish oil supplement industry.

“The evidence now suggests that a diet with a bit more omega-3 than that taken for heart disease prevention will reduce your risk of a cognitive decline but also reduce the risk of Alzheimer’s disease by almost 50 per cent,” he says.

Ryan can cite a battery of studies that appear to bear out the old wives’ tale that fish is good for the brain. One of the most compelling is a Swedish study published in 2009 in which 10,000 15-year-olds were monitored to assess the association between their fish intake and academic performance.

With the study adjusted to counter potential influences such as the parents’ own education, the results were startling. “The kids who rarely ate fish did worse academically than those who ate fish once a week,” says Ryan, “and the ones who ate fish twice a week did even better than the ones who ate it once a week.”

Ryan cites a US study published last year in the Journal of Nutrition, which found that of 300 adults aged 35-54, those with higher levels of DHA, a component of omega-3, tested better on non-verbal reasoning, mental flexibility, memory and vocabulary.

“The evidence is growing,” says Ryan. “I would say it’s as good now as the evidence for heart attack prevention was in 1990.”

But what are omega-3s and how can they protect against cognitive decline and Alzheimer’s? Omega-3s are a family of essential unsaturated fatty acids that include eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The body can’t make them very efficiently, so we have to consume them in our diet.

According to Ryan, omega-3s contained in fish oil, and its DHA component specifically, play a vital role in the structural integrity and function of our brains, with a lack of it increasing the risk of brain malfunction and disease.

In addition to the gradual loss of nerve cells in the brain as we get older, Ryan explains there are unwanted chemical side products that impair the function of these nerve cells, which harm memory and learning.

This leads to a drop in the ability of nerve cells to transmit signals from one to the other and this becomes part of a vicious cycle of cholesterol building up in the nerve membranes, with corrosive chemicals, known as free radicals, further damaging the membrane. Ryan says this vicious cycle responds to an increase in omega-3s in the diet, in particular, DHA.

He also says that DHA can prevent the formation of the brain “plaque” that causes Alzheimer’s while omega-3’s proven ability to reduce clotting contributes to the reduction of the risk of vascular dementia. “We know that omega-3s work in about 12 different parts of brain chemistry. So whether they just strengthen the brain so that this decline doesn’t happen, we don’t quite know,” says Ryan.

“It certainly does improve transmission across synapses, which helps in Alzheimer’s, but I think there is something else about the disease that we don’t understand. We don’t understand the core of what’s happening, though people are getting very close. I think that whatever is the core mechanism, omega-3s must have an effect, but what it is, we don’t know.”

Is there a resistance from drugs companies to such a simple solution? “Yes. You can’t patent omega-3s, so there’s no reason for a drug company to take it on,” says Ryan. So how can we get our hands on the stuff?

“Canned fish is one of the cheapest ways of getting it,” he says. “Mackerel, sardines and salmon all contain reasonable amounts of omega-3, except canned tuna. Wild tuna is full of it but they boil the tuna in the factory ships before they can it, so all the omega-3 is gone.”

Tinned fish in brine is best as sunflower oil can “knock out the optimal ratio” of omega-3 to omega-6 oils. When buying fresh fish, Ryan says mackerel is by far the highest source. “Wild salmon is an excellent source, but farmed salmon isn’t as good because they feed them artificially,” he say .

Such popular fish as cod, haddock and hake are “useless” from this point of view, he says, as they store the omega-3 in their liver and not their flesh.

So are we Irish eating enough of it? A North South Ireland Food Consumption Survey published in 2008 says not. The study found that the dietary intake of EPA and EHA was below recommendations, especially in younger adults.

“The evidence suggests that whenever you start to take it, it begins to have an effect,” says Ryan. “They’ve actually found a slight effect in the treatment of Alzheimer’s in the early stages, but . . . we don’t diagnose Alzheimer’s until several years in. What if you diagnosed it very early and gave them this? It might help. Those are the studies they are doing in America now.”

It seems that you can never be too young to take omega-3. Ryan cites a study published in 2002 in the journal, Paediatrics, which shows that children born to mothers who had taken cod liver oil during pregnancy and breastfeeding scored higher on mental processing at four years than children whose mothers had taken a placebo of corn oil.

“You can imagine a baby, it’s brain forming at an enormous rate, has a very big demand for omega-3,” he says, “particularly in the last third of pregnancy and the first two years of life.”

As well as eating oily fish, Ryan himself says he has taken a dessert spoon of high-strength omega-3 fish oil every day for more than 20 years. He takes it in the morning “when my taste buds are numb and with a coffee straight afterwards”.

“That would be enough to protect against Alzheimer’s, cognitive decline and heart attacks. I’m in my mid-60s and I’m writing very heavyweight science books,” he says. “I can read text books and take them in far better than I did when I was a medical student. So it seems to be working for me.”

Dr Frank Ryan was in Dublin to judge the brainfood.ie children’s fantasy writing competition

Spooning it: How much is enough?

For heart attack prevention and arthritis, the recommended daily dose is 800mg of omega-3s or about a dessert spoon.

For the prevention of Alzheimers disease or cognitive decline, the recommended daily dose is roughly 400mg or half a dessert spoon. People with a higher risk should take up to 800mg.

As fish oil slows blood clotting, those on warfarin or aspirin should consult their doctor before taking it.

For vegetarians who dont eat fish, omega-3 is now being manufactured from algae, with health food shops selling it as an oil or powder. Broad leaf vegetables should be eaten also to supplement EPA levels.