Dr. Tim Harlan aka Dr. Gourmet
Special for HealthKey.com
June 16, 2010
It's clear now that portion size is key to eating healthy. Over the past four decades this has become a major issue, with portions in restaurants increasing dramatically. Forty years ago a 32-ounce milk shake (that's a whole quart) with 1,160 calories would have been unusual. (1,200 calories is as much as some folks need in a single day.) There was no such thing as a Quarter Pounder or Whopper, let alone Double versions of these with cheese and bacon. Being served a huge plate of nachos would be rare.
These larger plates have distorted how we choose food on a day-to-day basis. For instance, one study evaluated the difference in the last two decades of how college students choose meals at a buffet. In one study begun in the 1980s and repeated in 2006, 177 students freely served themselves meals, which were then weighed. The portions were scored against the recommended portion sizes.
The portion sizes chosen for breakfast and lunch in 2006 were found to be more than 125 percent of the standard portion from the '80s. Overall, larger portions were taken by the 2006 students than by their 1984 counterparts. The proof that folks now have trouble is reinforced by the fact that much of the difficulty folks have is with figuring out what a larger portion actually is. They just can't tell the difference when the size is larger.
Brian Wansink, Ph.D., and his colleagues set up a study where they approached folks in fast food restaurants and asked them to estimate the number of calories in the meal that they had just eaten. The researchers had been watching and recording what the participants had eaten. Those being studied under-estimated the number of calories by 23 percent. When they looked at the estimates given for supersized meals vs. regular ones they found that those eating a smaller meal were able to accurately estimate the amount of calories they had eaten. This wasn't the case with larger meals where diners underestimated the calories they had just eaten by 38 percent. Dr. Wansink has been able to recreate these real-world findings in his lab numerous times.
So what works? Portion control. In 2004, the CDC surveyed over 2,000 adults who had tried to lose weight in the prior year. 587 had lost weight and kept it off. At the top of the five most common weight-loss strategies was smaller portions (others included reducing the amount of food eaten overall, more fruits and vegetables, fewer fatty foods, and no sweetened beverages).
Having a scale, measuring cups and spoons is key. Here's a guide to what one serving in the right portion sizes should look like for various ingredients: