This Week in Research: Diet Advice and Blood Money

A previous Johns Hopkins study showed that doctors are less likely to bond with overweight patients; now new research from Hopkins shows that patients can be just as prejudiced against their doctors.

According to the study, overweight and obese patients were more likely to trust weight loss advice from a doctor who was also overweight — and that diet tips from physicians with normal BMIs just didn’t carry the same weight. (Forgive the pun, couldn’t help myself.)

But in a result the researchers called “quite surprising,” overweight patients were also more likely to feel judged by obese physicians than their normal-weight counterparts. The study’s lead author, Sara Bleich, suggested that more research is necessary to find out exactly how obese and overweight doctors interact differently (or are perceived as interacting differently) with patients.

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Many big-deal health organizations (like, say, the World Health Organization) are firmly opposed to giving people money, gift cards, t-shirts, time off work, or other incentives for donating blood. That’s because previous studies have shown that rewarding people for blood donation may actually make people who are motivated to donate for altruistic reasons less likely to give blood, and may instead attract more unsavory characters — with more unsavory blood — to the donation pool.

But that’s not true, according to recent research out of Johns Hopkins’ Carey Business School. For the study, researchers examined data from nearly 100,000 donors at 72 Red Cross blood drives in Ohio. At half the blood drives, donors were offered gift cards; at the other half, they received no incentives.

In contradiction to earlier studies — which, incidentally, were conducted with hypothetical surveys, not real-life situations — the incentives increased participation: a $5 gift card increased the likelihood of giving among people with a history of donating by 26 percent; and a $10 gift card increased it by 52 percent. At a time when international blood stores are running low, incentives might make a big difference.

“Debates on ethical issues around giving rewards for donations are inevitable and should be encouraged,” the authors concluded. “But there should be little debate that the most relevant empirical evidence shows positive effects of offering economic rewards on donations.”