No one likes to be nagged, but that's often what health advice seems to do. There are all those don'ts (as in smoke, eat too much, gain weight). And the dos (exercise, eat fruits and vegetables) are predictable, even for people who don't mind them. Live longer, live healthier, you say? Okay, but what a chore and a bore!
According to the Harvard Health Letter, health researchers are reporting results that suggest maybe you can have your health and enjoy yourself, too. Studies have elevated coffee to health-drink status by linking it to a reduced risk of dementia and Parkinson's disease. Dozens of findings have shown that alcohol and chocolate may have cardiac benefits. Sex, sleep and a social life seem to have all-around benefits.
Never has high living looked quite so healthful, although it's high living on a leash. The permission to indulge almost always comes with a reminder about doing everything in moderation.
Dozens of studies have shown that moderate alcohol consumption protects against heart disease and stroke. Drinking increases "good" HDL cholesterol, reduces factors in blood that make it more likely to clot, and may directly affect blood vessels, keeping the linings smooth and pliable and thus less vulnerable to atherosclerosis. European researchers reported interesting findings in 2008 that show a connection between alcohol intake and higher blood levels of omega-3 fats. Indeed, temperate tippling has been associated with everything from greater bone density to less risk for Alzheimer's disease and vascular dementia.
Moderation gets mentioned rather immoderately in the pro-alcohol medical literature because drinking too much is patently ruinous. Triglycerides and blood pressure go up. Binge drinking can lead to stroke. The myriad troubles associated with alcoholism don't need to be recounted here. Moderation is flexibly defined, but the American Heart Association guidelines are often cited: for men, one to two drinks a day; for women, just one. The limit is lower for women because they tend to be smaller and break down alcohol more slowly than men. A drink is defined as a 12-ounce beer, 4 ounces of wine, or 1.5 ounces of 80-proof liquor.
Women do need to worry about alcohol increasing breast cancer risk. Alcohol may drive up estrogen levels, and estrogen seems to play an integral part in the development of many breast cancers. Epidemiologic studies have consistently found an association between alcohol consumption and breast cancer risk, although at moderate amounts (the drink-a-day level), the risk is small. The good news: folic acid may help offset the breast cancer risk posed by alcohol, so women who drink are encouraged to get an extra 400 micrograms per day.
Woody Allen saw it coming with his joke in Sleeper about researchers deciding that hot fudge was good for us after all. A steady stream of studies has won chocolate cardiovascular laurels by showing that it improves blood flow through arteries that supply the heart and the brain. Chocolate's winning ways continued in 2008. Harvard researchers found that two weeks of enhanced chocolate intake quickened blood flow through the middle cerebral artery. And Italian researchers reported a possible connection between eating dark chocolate and low levels of C-reactive protein, a marker for inflammation.
Not every study has been a thumbs up: researchers at the National Institutes of Health concluded that chocolate did not decrease blood pressure or improve insulin sensitivity in a two-week study of people with high blood pressure. Moreover, the chocolate-as-healthful dream needs a couple of reality checks. The most likely explanation for chocolate's good effects is that cocoa beans contain substances called flavonols (specifically, catechin and epicatechin, which are also found in tea) that stimulate production of nitric oxide, a chemical that relaxes blood vessels. In the studies cited above, researchers have used "flavonol-rich" chocolate. But typically, the processing of cocoa beans into chocolate removes flavonols. Dark chocolate may have more flavonols than other types, but you can't go just by darkness. Some companies have started to market products advertised as preserving the cocoa bean's flavonol content (for example, the Cocoavia bars made by Mars, a company that has funded a lot of the pro-chocolate research).
Another caveat: the sugar and fat content of chocolate candy translates into calories (more than 200 in a 3.5-ounce bar of expensive dark chocolate). And some of the fat in many chocolate bars is the unhealthful saturated variety.
For the health conscious, a cup of coffee was once a somewhat perilous pleasure. Early studies showed a connection between coffee and heart attack, a worry that seemed to be validated by coffee's ability to quicken the pulse. Some other studies cast the gloomy shadow of cancer risk.
But the cancer research was flawed or overturned by more definitive findings. Not all the evidence has been exculpatory, however. A Harvard study published in 2008 found no overall association between caffeine consumption and breast cancer risk, but there were hints of a connection in women with a history of benign breast disease and those whose tumors were estrogen- and progesterone-receptor negative.
Meanwhile, the coffee–cardiovascular disease research has done an about-face: now the gist is that coffee drinkers seem to be less likely to have heart attacks and strokes and develop diabetes than nondrinkers. The caffeine in coffee does constrict blood vessels (that's why it can help with headaches caused by vessels that have dilated) and may increase your heart rate a little, but those are transitory effects. Coffee has other ingredients (specifically, phenolic compounds) that seem to cancel out whatever negative effects chronic exposure to caffeine might have. Those other ingredients might explain why decaffeinated coffee has shown benefits similar to the caffeinated version in several studies.
Study results indicate that coffee drinking may tamp down the risk of developing Parkinson's disease. No one is sure why, although it's been suggested that caffeine affects receptors in the basal ganglia, the part of the brain most damaged in Parkinson's. Other studies are brewing hopes that coffee may affect our brain cells in ways that diminish risk for dementia and Alzheimer's disease.
The good healthkeeping seal of approval for coffee comes with cautionary notes. Pregnant women are still advised to limit, if not avoid, caffeine intake, although the American College of Obstetricians and Gynecologists' position is confusing. Its patient brochure says "some studies suggest drinking three or more cups of coffee per day may increase the risk of miscarriage," but adds "there is no proof that caffeine causes miscarriage." Another caution: unfiltered coffee — which includes coffee drinks made with espresso — may increase "bad" LDL levels because some harmful substances in the coffee don't get filtered out. There's nothing wrong with the occasional latte or cappuccino, but overdoing it may mean a return to the bad old days when coffee was cardiovascularly suspect.
Obviously sexual arousal and orgasm is a source of great pleasure and a sense of well-being, but even after the immediate glow fades, there may be residual health benefits. Sexual activity can cause heart attacks, but it's been estimated that chances are only one in a million that a man who has had a heart attack will have another during or immediately after sex. Meanwhile, other research has suggested that frequent sexual intercourse (twice a week) is associated with reduced heart attack risk, even after making the statistical adjustments necessary to account for the fact that men who have sex that often are healthier over all. Conventional sexual activity revs up the metabolism, but only so far: orgasms, minute for minute, create the same exercise workload as walking at a pace of three miles per hour. The cardiovascular demands of sex have been compared to walking up two flights of stairs. Even if sex isn't great aerobic exercise, exercise may make for better sex: several studies have shown that moderate exercise increases genital response to erotic stimuli in women.
Marvin Gaye sang about it, but you can also find bits and pieces of evidence in the medical literature of the power of sexual activity to fix medical problems. An Israeli neurologist published a case report about two male patients whose headaches went away after sexual intercourse or orgasm (although sexual activity as a cause of headaches is far more common). Researchers have reported that women who have intercourse regularly are more likely to have regular menstrual cycles. And sex may be a pretty good germ fighter. German investigators reported that white blood cell counts went up in men after sexual activity. That's in keeping with other research suggesting that sex gives the immune system a boost.
Granted, these studies are too small or short to be anything but speculative and suggestive. The fact is that much of the research into health and sexual activity has focused on how illness adversely affects sexuality, a worthy topic, but it might be revealing to turn the tables and pay a little more attention to the vice versa: how sexual activity may have ameliorating effects on illness.
We're resting easier (sometimes longer) these days because of the laurels that sleep is winning for its health benefits — or, more precisely, because of the evidence of all the bad things that can happen when we don't get enough of it. Several epidemiologic studies — the kind that involve following thousands of people over many years — have shown that "short sleepers" put on more pounds than people who sleep seven to eight hours a night, which is the amount that seems optimal for most adults. Other studies have linked skimping on sleep to the high-risk pool for heart attacks, diabetes, and early death. The risks are more pronounced for people who sleep less than five hours a night, but the danger seems to extend to those averaging less than six. It's easy to poke holes in epidemiologic evidence, but short-term experiments in sleep deprivation have lent credence to these findings. When healthy volunteers stay awake for long stretches, it wreaks hormonal havoc: levels of cortisol, a stress hormone, go up, and leptin and ghrelin, hormones that influence appetite, get thrown out of whack.
Of course, lack of sleep has a very direct effect on the brain, influencing memory, mood, and attention. We've all experienced grogginess after not getting enough sleep. Dr. Charles A. Czeisler, a Harvard sleep expert who has campaigned for limiting the working hours of medical residents, says averaging four hours of sleep a night for four or five days results in the same level of cognitive impairment as being legally drunk.
Can you sleep too much? Several of the epidemiologic studies of sleep show that long sleep (nine hours nightly or more) is associated with just as many health problems as short sleep, if not more. But it's probably more often the case that an underlying illness (depression is a prime example) causes people to sleep more, not the other way around.
We could all use a little help from our friends, but just having them may also help us stay healthier. A slew of studies has shown an association between social networks and good health. Cognitive decline, high blood pressure, the risk of dying after a heart attack — they've all been linked to social isolation and loneliness. Sorting out cause and effect is difficult. Ill-health itself can strain social ties, although it's also true that coworkers, friends, and relatives tend to rally around people who have strong social networks prior to getting ill. Teasing apart the objective (not having someone to take you to the doctor, for example) and subjective (being lonely) aspects of isolation is yet another conundrum. Regardless, tending to friendships, family, and community life is a good habit to cultivate for health and other reasons.