You Are What You Eat, Revisited

A new four-year study from Brigham and Women's Hospital and the Harvard Schools of Medicine and Public Health has identified some specific foods and food types that are more responsible for the excess weight we gain than are most others. This prospective, longitudinal study was published in the June 23 New England Journal of Medicine.

Over the four years of the study, participants put on an average of about 0.8 pounds per year, or 3.2 pounds over the entire study. Perhaps a gain of 0.8 pounds per year doesn't seem like too severe a problem, but over 20 years' time, it's going to swell up to 16 pounds--potentially enough to contribute to becoming overweight and to health challenges such as diabetes, heart disease, and cancer.

The No. 1 weight-gain perpetrator

Perhaps surprisingly, the researchers discovered that the food most strongly linked with the participants' gains in weight was the humble potato chip. Yep, this mild-mannered but ubiquitous snack food was responsible for about one-half of the 3.2 pounds that the average study subject put on over the four-year period.

Some other consumable culprits

Overall, if eaten in large quantities, potatoes themselves were responsible for 1.28 pounds of an average participant's 3.2-pound weight gain. Likewise, these three other food categories were each believed to also be responsible for packing on an additional pound of weight during the study:

• sugar-sweetened beverages
•  unprocessed red meats
•  processed meats

Behaviors can put on weight too

The study also mentioned several other factors besides diet that were involved in gaining weight, including

• drinking alcohol -- for each alcoholic drink averaged per day, participants gained 0.41 pound by the end of the four years
• stopping smoking -- participants who quit during the study put on 5.17 pounds over four years
• watching TV -- for each hour of TV averaged per day, participants gained 0.31 pound over the four years

On the flip side

During the four-year study, the researchers also identified some foods that were significantly linked with weight loss, with yogurt at the top of this "good" list. All of these values in pounds signify the weight lost from averaging one serving of a particular "good" food per day over the four-year span. All values were statistically significant (P <0.005).

• eating an average of one serving of yogurt over four years was associated with a total loss of 0.82 pound
• nuts, a total loss of 0.57 pound
• fruits, a total loss of 0.49 pound
• whole grains, a total loss of 0.37 pound
• vegetables, a total loss of 0.22 pound

Including more of these foods in your diet over time might not result in dramatic weight loss, but may, in the long run, result in slimming of the waistline and decreasing your risk for the significant diseases mentioned above.

Other things associated with weight loss

Regular physical activity was linked with a 1.76-pound loss of weight over the four-year study period. No surprise, therefore, that exercising, as well as stopping smoking and cutting back on TV and alcohol also appeared to be important in keeping the weight off.

My take on this study

• Although these findings might not seem like earth-shattering news, this study does pinpoint the healthiest weight-loss foods that you must include in your diet--foods such as yogurt (soy yogurt if you're vegan or have issues with dairy), fresh fruits and vegetables, and whole grains.
• Nuts are healthy, of course, but moderation is encouraged if you're having weight challenges (that is, no more per day than a 1/4-cup serving) since they're chock-full of calories. (A person innocently snacking on a bowl of nuts has been known to consume over 2,000 calories in one sitting!)
• Probiotics, or healthy bacteria, might be a factor in yogurt's weight-healthy benefits, since recent studies of these good bacteria have revealed that they promote weight-friendly hormones.
• Of course, I'd go with the non-sugary kind of yogurt, especially the Greek and Icelandic styles, which have much more protein than regular brands and satisfy your appetite much better.
• Prebiotics--the healthy foods that our bodies' good bacteria like to eat--are found in fresh fruits (bananas are super-high in them), vegetables, and whole grains.
• Prebiotics might also help keep our gastrointestinal tract happy, which is always a good thing, and might be weight friendly as well.
• Moderation is crucial. There isn't one magical food or ingredient that we should be eating all of the time. When you're shopping for fruits and vegetables, buy all the colors of the rainbow, so you will be eating a whole array of different vitamins, minerals, and antioxidants (cancer-fighting agents).

To your health, dear readers!