Search results: app

Several people, among them Kerry Trueman of Eating Liberally, asked my opinion of John Tierney’s column about Gary Taubes’ new book, Good Calories Bad Calories, in today’s New York Times. Taubes’ book arrived while I was in India and I can’t really comment on it until I have had a chance to read it. I gather from Tierney’s piece and Gina Kolata’s review of it on Sunday that it comes down hard on carbohydrates.

I continue to be impressed by how difficult it is to separate the health effects of fat, carbohydrate, and protein from the calories they provide, the foods that contain them, the diets as a whole, or the rest of the lifestyle that goes along with the diet. Finding out what people eat is hard to do. Determining the health effects of dietary factors or patterns is even harder since humans make such awful experimental animals. Plenty of things about human nutrition are reasonably well established–the basic nutrients that are required and the amounts that prevent deficiency diseases, for example. But it is much trickier to figure out the effects of nutrients on chronic diseases that are also affected by activity levels, cigarette smoking, alcohol use, and social factors such as poverty, stress, and lack of control. So I can’t help but be skeptical of journalists who think they have answers to questions that scientists have been grappling with for years.

In a situation in which questions remain, is it better to say nothing or to give the best advice possible based on existing knowledge? Intelligent people may differ on this point but I am convinced that people really want to know what diet is best for their health and want help making food choices. What seems amazing to me is that despite decades of arguments over fat v. carbohydrate, basic dietary advice for preventing chronic diseases hasn’t changed in 50 years. I summarize this advice in What to Eat as don’t eat too much (eat less, move more); eat plenty of fruits, vegetables, and whole grains; and don’t eat too much junk food. This seems like a pretty good approach backed up by plenty of research.

Oh, and the calorie question. It’s not that people are overeating 50 to 100 calories a day (the amount in one or two Oreo cookies) and gaining weight. Most bodies can easily compensate for small differences in caloric intake and output. But, as I hear from pediatricians all the time, kids these days are consuming hundreds of calories more than they need, and sometimes thousands. Metabolism–in kids or adults–just can’t handle that level of overload. In that situation, carbohydrates may be harder to handle than fats, but both will end up in the body as fat if those calories aren’t used up in physical activity.

Fortunately, my precepts leave plenty of room for enjoying delicious food, and aren’t we lucky to have so much around.

In case you missed CNN’s weekend investigative report on America’s obesity epidemic, you get another chance online. I was interviewed for it and appear for 5 seconds right at the beginning. I’m always suspicious of programs that show lots of pictures of overweight people (with heads discreetly cut off); they usually miss key points as well as being insensitive. I’m curious to know what you thought of it. CNN went to a lot of trouble to do all those interviews and all that filming. What did you learn from it? Do tell.

Today’s question: “Dr. Nestle, any suggests of a group fighting listeria/listeriosis to fund? Given your expert stature, you are my best source. ..My father was Dxd [diagnosed] with this around May 1 after being admitted to hospital apr 19 – But the suffering from it and cost of it – what if my mom hadn’t had a spare $100,000 – unbelievable. And I am sure insurance covered another million or so. In 5 mos.”

Here’s my thought: Listeria are among those newly emergent bacteria that arrived along with industrial food production. They are especially nasty because they grow happily at cold temperatures. I’m not aware of groups specifically devoted to fighting this one, but there are excellent groups working on food safety issues in general. One is STOP–Safe Tables Our Priority–created by mothers of children who died from the effects of eating hamburgers contaminated with E. coli 0157:H7. The food safety issues are the same. Both bacteria would be less of a problem if we had a better food safety system. But let’s ask: does anyone know of any groups working specifically on Listeria issues?

I’ve just gotten a notice that a big study in Critical Reviews in Toxicology gives aspartame a clean bill of health; the reviewers judge it safe at current levels of intake and find “no credible scientific basis” to think otherwise. This comment refers to contrary studies first published a year or so ago and confirmed again this summer by an Italian group (see their paper in Environmental Health Perspectives). This group claims that aspartame causes cancer in rats when consumed at levels typical of those in soft drinks. The Critical Reviews analysis is the most recent of many other such studies discounting the methods and opinions of aspartame critics. Will this latest study–at long last–put the matter to rest? I doubt it. The Critical Reviews analysis was funded by the maker of aspartame, Ajinomoto. Even though its authors were not told this, and the sponsor was not involved in the review, the study gives the appearance of conflict of interest. This kind of sponsorship is not helpful. My own view (which I discuss in detail in What to Eat) is that aspartame probably is safe at current levels of intake. But so what? It is an artificial sweetener. I don’t like anything artificial when it comes to food and I much prefer sugar (in moderation, of course).

Without having to get into First Amendment issues, a federal judge agrees with the National Restaurant Association that New York City may not require fast-food restaurants that already have nutrition information available to post information about the calories in their products on menu boards. BUT: the judge also says that cities and states certainly can require calorie labeling as long as the rules apply to all chain restaurants with 10 or more outlets whether or not they make nutrition information available voluntarily. Good news? Will this encourage more cities to pass such rules? Can’t wait to see.

Here’s what the Wall Street Journal has to say about this. And the New York Times.

I haven’t thought carefully about this question since I first read Francis Moore Lappe’s Diet for a Small Planet in the 1970s: “I have a question…about growing grains for livestock feeding: When corn, for example, is grown, it has a k/cal value, or an amount of caloric energy that I assume can be counted for human nutrition. As it is used for feed, is caloric energy lost in the transfer? In other words, is the resulting food (all the butchered and eaten parts of a cow, for example) similar in energy content to the edible feed that went into it? I assume we lose some caloric value along the way, but how much? To me, this has all kinds of implications that I’d like to ponder, including the implications of this from the (admittedly broad) prospective of global hunger.”

This is about “feed efficiency ratios”–the amount of food it takes to make a pound of animal or a pound of us. Let’s hear it for Wikipedia, which has a nice summary with a reasonable reference. It takes more grain to make beef than pigs, chicken, or fish. A lot of those animals are not usable for food (maybe half a beef carcass, for example) and we have our own problems with efficiency. The calories listed in food tables are pretty much what we can use and the better tables specify how well the meat is trimmed. Good question!

The FDA is meeting this week to consider a red, yellow, green system for labeling foods according to their degree of healthfulness. Here’s what the New York Times has to say about this. This is, of course, would be much like the Hannaford supermarket “follow the stars” program, about which several of you have strong feelings (see comments under entries for Supermarkets and Labels). In the early 1990s, Center for Science in the Public Interest did a fold-out pyramid designed to be put on school cafeteria tabletops. This listed foods on green (anytime), yellow (once in awhile), and red (seldom) sides of the pyramid. As is always the case with these kinds of approaches, the line between categories is a thin one and subject to much argument and manipulation. The FDA proposed something much simpler about five years ago: to put the entire number of calories on the front of packaged foods. What a good idea! It still hasn’t happened. Don’t hold your breath for this one either.

My article, “Eating Made Simple,” appears in the September issue of Scientific American along with a podcast. Enjoy! The journal’s website also has an excerpt from What to Eat–Chapter 5 on the produce section: “Genetically Modified, Irradiated, and Politicized.” Enjoy that too!