In praise of the lowly apple
You see them, and you sniff. Apples are as boring, as generic as a fruit can get. They lack the cachet of red grapes, oozing life-extending resveratrol. Unlike blueberries or pomegranates, they are not celebrated for supplying palate-pleasing megadoses of antioxidants.
So why did some wit observe, “An apple a day keeps the doctor away”? That question has been on the mind of Bahram Arjmandi, professor and chair of the department of nutrition, food and exercise sciences at Florida State University.
His answer, presented at the Experimental Biology 2011 meeting in Washington this week, admittedly seems too good to be true: Apples have a profound effect on total cholesterol, and also on the “good” and “bad” types of cholesterol. They caused a major reduction in inflammatory proteins that are implicated in a number of serious diseases.
Not only does this “medicine” taste good, but unlike cholesterol-control pills, it does not attack the liver. And last we heard, you can buy them without a prescription.
“An apple a day” or a “fateful fruit”?
In the Bible, “the apple was an evil food in the story of Adam and Eve,” Arjmandi says, “then someone said, ‘An apple a day…’ and that gave them a positive image. I thought, if there is that saying, there might be a reason for it, but you’d be amazed at how little has been done in clinical studies.”
To get answers, Arjmandi rounded up 100 women who had just passed menopause — a time when dropping levels of estrogen lead to unhealthy changes in cholesterol levels that allow women to catch up with the male rate of cardiovascular disease.
Randomly dividing his volunteers, Arjmandi asked one group to supplement their normal diet with dried prunes. The treatment group got one-a-day packages containing 75 grams — about 2.5 ounces — of dried apple.
Arjmandi used dry apples rather than the equivalent one or two fresh apples as a way to standardize the “dose,” but he says fresh fruit is likely to be even more healthy.
If the object of these tests was a pill, the results after one year would certainly boost the stock of the drugmaker: among the apple-eaters, total cholesterol fell by 14 percent and low-density lipoprotein (LDL, the harmful fraction of cholesterol) fell 23 percent. High levels of both total cholesterol and LDL are linked to damage to blood vessels, heart attacks and strokes.
Meanwhile, the level of a protective type of cholesterol called high-density lipoprotein (HDL) rose 3 to 4 percent.
(Anti-) inflammatory results
Moving beyond cholesterol, the level of C-reactive protein fell 32 percent. “This is significant, and not just in a statistical sense but in clinical relevance,” says Arjmandi. “CRP is associated with inflammation, and is considered a marker for cardiovascular disease, cancer and Alzheimer’s disease.”
Seeing such a major reduction from such a simple “treatment” is “amazing,” Arjmandi said.
And although the women in the test group were eating about 240 calories of dry apple each day, they lost an average of about three pounds over the year — perhaps because apple makes people feel full.
The study was partly funded by the United States Department of Agriculture, and got no funding from the apple industry. Although the report, as far as we know, has not been peer reviewed, talks at scientific meetings are routinely used to introduce new studies and new concepts.
And the active ingredient is…
What makes apples so healthy? Although both pectin, a soluble fiber, and chemicals called polyphenols are thought to confer health benefits, Arjmandi says, “an apple is more than these compounds. I’ve been working on functional foods [which give health benefits] for 20 years, and I find it’s not good to approach whole fruit or whole vegetables like drugs. If you isolate the component chemicals and take them, you get some benefits, but you will deprive yourself of greater benefits.”
Are some apples better than others? “For pectin, the firmer the better,” says Arjmandi. “Otherwise, most varieties, from jonathan to red delicious, give more or less the same benefit.”
Polyphenols are concentrated in the peel; pectin is found throughout the apple, he adds.
Last question: Did the study participants get sick of snacking on dry apple day after day? Some did, and quit the study, but “those who like them became addicted,” says Arjmandi. “The longer they were on it, the more they liked apple. Afterwards, some contacted us to ask if we can provide them with apple.”
Supermarkets, actually, carry apples side-by-side with other non-prescription produce.
Based on these results, Arjmandi would like to test the apple-a-day prescription more broadly. “I’d like to do a multi-state trial. Eating 75 grams of apple is not that difficult, and finding people with moderately high cholesterol is not that difficult.”
– David Tenenbaum