Posted by kathryn in Health News, Antioxidants, A Balanced Diet and Vegetables

Back to one of my favourite subjects, why vegetables are good for you. A recent six-year study has found that diets high in vegetables are associated with slower mental decline in older people.

The study, part of the Chicago Health&Aging Project (CHAP), took place between 1993 and 2002 and followed almost 2,000 people (male and female) aged 65 years and over. Over the six year period, the participants cognitive function was measured on three occasions, using tests of short and long-term memory and flash-card exercises using numbers and symbols.

“Compared to people who consumed less than one serving of vegetables a day, people who ate at least 2.8 servings of vegetables a day saw their rate of cognitive change slow by roughly 40 percent, said study author Martha Clare Morris, ScD, associate professor at Rush University Medical Center in Chicago, Illinois. “This decrease is equivalent to about 5 years of younger age.”

A serving of vegetable was classified as either half a cup chopped, or one cup of leafy vegetables, like spinach. Diets high in fruit, but not vegetables, did not give the same benefits. Green leafy vegetables like spinach and silverbeet seemed to give the most benefit, followed by yellow / orange vegetables such as carrots and pumpkin and then the brassica vegetables, broccoli, cabbage, cauliflower and brussel sprouts.

Vegetables are higher in vitamin E and contain different antioxidants to fruit, such as carotenoids, different flavonoids and so on. Vitamin E itself is a potent antioxidant, which protects against cellular damage, including in the brain. The study also points out that vegetables are more often eaten with fats – for example with fish, or oil from a salad dressing, or cooked in olive oil – which may assist in the absorption of antioxidants.

And it’s worthwhile increasing your vegie intake now, as the people who raised their vegie intake during the period of the study, also experienced a significant slowing of mental decline. Plus, the older the person, the greater the impact of eating more than two servings of vegetables a day.

As well as preventing vitamin and mineral deficiencies, improving cardiovascular and digestive health, extending life expectancy and protecting against macular degeneration, it seems that vegies also keep your brain younger. Yet another good reason to include more of them in your diet.

Oh yes, and 2 – 3 pieces of fruit per day, while not protecting againt mental decline, are still an important part of a healthy diet, just think fibre, vitamin C, potassium and so on.

Further Reading:

• Morris, MC, Evans DA, Tangney CC, Bienias JL, Wilson RS, Associations of vegetable and fruit consumption with age-related cognitive change, Neurology, 2006;67:1370-1376.
• Rush University’s press release.
• News reports: The Australian and Kansas City News.
• For ideas on ways to increase your vegie intake check out these blogposts: why you need your vegies, more on carrots and how to eat more vegetables, carrot fritters, fresh vs frozen vegetables, getting kids to eat fruit and veg, or the Go For 2 + 5 campaign.

Technorati tags: cognitive decline, mental decline, vitamin E, Aging, aged health.

04 November, 2006