Eater’s Digest

Eat, drink, and be wary: With the aid of a registered dietitian, we sort through today’s nutritional conundrums and arrive at some answers
Eater's Digest
Illustration by Joseph Daniel Fiedler

In the world of health and nutrition, conflicting studies can make consumers’ heads spin. Is margarine or butter better? Is drinking red wine truly beneficial? Are energy bars a good bet for on-the-go nutrition? We spoke with Bethany Thayer, a registered dietitian and national media spokesperson for the American Dietetic Association, to help clear the air about eating well.

For years, coffee was demonized for raising blood pressure, but it does contain antioxidants. Provided you don’t take them with cream and/or sugar, are a few cups a day fine?
The message now seems that moderation — one to two cups a day — is probably OK. Would I call it a healthy choice? I don’t think I’d go that far. As long as at an individual level you’re able to tolerate the caffeine, a couple of cups a day is probably not a health risk.

Red wine has gotten a lot of good press lately because of resveratrol, which is supposed to keep blood vessels open and is said to repair damage from free radicals. Since resveratrol is present in grapes, wouldn’t it be as effective to drink grape juice instead?
Yes, for that purpose — the resveratrol or other antioxidants that are in the grapes. Alcohol is a funny thing, because you’re not going to find a health professional who recommends it because of the potential for abuse. But we do have some research that [suggests] people who drink wine in moderation — two glasses a day for men and one for women — seem to have a lower risk for mortality, and also seem to have improved high-density lipoproteins [HDL], the good cholesterol. That’s why you get some people who say red wine may be better.

We all know that sugar-infused sodas are terrible, but people gulp down the sugar-free variety, thinking there’s nothing wrong with it. Is the jury still out on artificial sweeteners?
Artificial sweeteners are probably one of the most studied additives to our foods, and the research that keeps coming back is that they’re safe. A very, very small percentage of people do have an intolerance of aspartame [an artificial sweetener], but they seem to know it as soon as it’s consumed.

Tuna is high in protein, but there’s concern about mercury content. Which kind of tuna is more likely to contain higher levels of mercury?
Albacore is the one that tends to have a bit higher concentration of mercury. Chunk light is a little safer. But fish is so good, and has those great Omega 3s. Just don’t have a can of tuna fish every day.

Is margarine or butter preferable?
It depends on the oil and consistency. With stick butter versus stick margarine, I’d choose butter because of the trans-fats in the margarine, even though butter is higher in saturated fat and cholesterol. When it’s stick butter versus softer margarines [tub, liquid], I’d choose margarine because the trans-fat content is generally low to none. But the best choice is using liquid oil instead of either, like dipping bread into olive oil.

Is there any proof that there’s one type of tea, be it black, red, green, white, that’s better than others?
No. They all have their own vital chemicals, their own antioxidants, and they all seem to be decent choices. It’s a taste preference.

There’s been a lot of hype about energy bars, but so many contain a lot of sugar. Could you comment on their effectiveness?
For people who have little time, they’re often thought of as a way to get good nutrition. The thinking is, “Everything we need is in these bars, and if I have one, I’m good to go.” In general, most of them appear to be candy bars with vitamins and minerals added.

Many people think that organic foods are inherently better than non-organic products. True?
There doesn’t appear to be anything nutritionally superior with organic products, so an organic pear doesn’t necessarily have more nutrients than a non-organic pear.

But the organic pear may not have the residue from insecticides.
Right, and that’s a concern. But whether it’s organically grown or not, you still need to wash it. Just because it was organically grown doesn’t mean it doesn’t have some contaminants on the outside. It may not be an insecticide, but it could be E. coli or something like that.

Flavonol in chocolate has been highly touted, but is dark chocolate always better than milk chocolate?
No. It’s how that chocolate has been processed and how it’s been made, and where the cocoa came from. [Eating chocolate] has become an excuse: “Now we can eat chocolate and feel good about it.” But in the studies about the benefits of flavonol, the people were eating about 4 ounces of chocolate a day, and that’s getting up around 500 calories. There are other things we can do to make a bigger impact on our health.

There’s a good deal of discussion among health professionals about controlled indulgence versus simply avoiding some foods. In your view, are there foods everyone should steer clear of?
No. I’m a big proponent of the idea that all foods can fit into a healthy diet. For me to say nobody should ever eat something again, I don’t think that’s realistic. … You can look at foods like doughnuts or hot dogs and ask what the nutritional benefit is in eating those, but eating is more than just physical; there’s the psychological and social aspect to it, too. We need to consider all of those things when we look at someone’s diet.