Fruit a key in the fight against age

The Orchadist December 2002
Alison Kay

American neuroscientist Dr James (Jim) Joseph has just been in New Zealand to tell us why.

His four years of research have shown the high antioxidant levels in blueberries can improve memory and motor control in aging rats. More recent experiments with humans suggest the same may be true.

Jim was in New Zealand briefly last month as guest of Blueberries New Zealand. His blueberry research is included in The Colour Code, a nutrition book for the layperson that takes the 5+ a Day fruit and vegetable concept a step further.

All plants contain pigments for colour and a range of compounds called phytochemicals that create flavour, scent and ward off bugs. Nutritionists now believe phytochemicals can also contribute to good health in humans.

As Jim says "Your mother was right when she told you to eat your greens. The book tells you why.

Jim has a wicked sense of humour and admits to being politically incorrect at times. But there is no doubting his passion for the subject of his research.

Why blueberries?

As a neuroscientist, Jim has studied aging for 25 years and had become interested in the effects of diet on aging. He carpooled with a colleague at Tufts University, Boston, who had devised a way to measure the antioxidant levels of various foods. During a carpool conversation Jim told his colleague that he would be willing to research whatever had the highest antioxidant levels. The winner was blueberries and his research began four years ago.

Blueberries have antioxidants and anti-inflammatory properties which make them one of the best foods for protecting the brain as people age. There is even a chance that they may help inhibit the onset of Alzheimer's disease.

In two controlled experiments Jim found that aging lab rats and mice on blueberry-supplemented diets showed slower deterioration of memory and co-ordination than those on standard diets.

He devised a "Rat Olympics" exercise in which blueberry-fed rats not only out-performed other rats but also showed improvements in co-ordination and balance.

A second experiment involved mice genetically altered to develop Alzheimer's disease. Those fed a blueberry-supplemented diet from weaning to 12 months (middle age in mice) out-performed the control group in exploring a y-shaped maze.

"This doesn't guarantee that blueberries will prevent or delay the onset of Alzheimer's disease in people. It's just an early indication that they might be helpful." Jim says in The colour Code.

"The mice were given blueberries before they developed any pathology. Once you've got the disease it may be too late."

Jim is careful not to make statements or draw conclusions that can't be supported scientifically. However he says preliminary research on people recruited from senior citizens' centres in Boston suggest very similar results to his lab tests. Papers will be written this northern winter for spring publication, detailing the human research techniques and findings. From there he hopes funding will be made available for formal research.

Working with colleagues at Tufts University, a computer test was designed for the human guinea pigs to use on the Internet at home. It involved reactions to stimuli and, once base patterns had been established, one group began eating blueberries at the rate of one to two cups a day.

"After three months, we saw improvement in reaction speed, the same as with the rats. We crossed the groups over so that those on the placebo began eating blueberries and the first group went onto the placebo.

"The interesting thing was that the people who went off blueberries maintained their faster reaction speed."

Jim noted the blueberry eaters also recorded "feel good scores.

"People reported feeling healthier and happier. They were sleeping better. We found women reported their feel good scores were going up and men reported faster reaction speeds even though they were also feeling good and the women also had faster reactions. It was interesting that women focused on feelings and men on reactions."

For the past 18 months Jim has also been focusing on why blueberries are so effective.

"We have been looking at some real technical stuff relating to neurons and the brain. As we age neurons don't talk to each other and that translates into bad memory and bad motor performance. It used to be thought that the brain couldn't generate new neurons. We now know that neurons are made throughout life but the process slows down. Blueberries turn that on again."

Jim says other berry fruit such as strawberries and cranberries also have the anit-oxidant and anit-inflammatory properties but blueberries stand out. He and his wife start everyday with a blueberry smoothie.

Diet needs to be high in fruit and vegetables

"But even blueberries won't offset a bad diet or unhealthy lifestyle. We can't stress enough the importance of eating a diet high in fruit and vegetables but exercise and healthy living are also vital."

For blueberry growers, Jim Joseph's research findings have proved a shot in the arm.

"It's hard to measure that value of the story," says Blueberries New Zealand chairman Dan Peach, of Matangi, near Hamilton.

Consumers are discerning

"Consumers are discerning about healthy foods and need scientifically sound research findings before they'll believe the advertising slogans.

"This is ground-breaking research. It's only just being talked about now. As it becomes available to world consumers of blueberries, demand will increase."

Waikato is the country's largest blueberry growing region with the main harvest season running from December to March.

Most produce is exported although domestic consumption is rising about 15 percent a year. Dan says blueberry plantings and production have been rising steadily over the past four years.