Limit consumption of energy-dense foods. That’s the advice from the latest international report on diet and cancer published by the American Institute for Cancer Research. The recommendation — aimed at promoting weight control — was included in the cancer-focused report because of the convincing link between overweight and several types of cancer.
The “energy-dense food” category referenced in the report includes foods that are concentrated in calories, usually because they are high in fat, processed carbohydrates and/or added sugar. Note, however, that some energy-dense foods — namely, nuts and seeds — are relatively unprocessed and supply many beneficial nutrients. These foods are not linked to weight gain when consumed moderately as part of a healthy diet.

Most Americans, however, are choosing the other kinds of energy-dense foods — those that the research links to an increased chance of weight gain, overweight and obesity. One popular consumer solution: Choosing reduced-fat or fat-free forms of the same foods. But these lower-fat options aren’t always lower in calories, particularly when they are consumed in jumbo portions.

A typical blueberry muffin purchased before the “super-sizing” of America’s food supply would have measured less than three inches in diameter and might have contained about 250 calories. Today, however, many bakeries and coffee shops serve muffins with twice the calories of the old-fashioned size. Even if a consumer chooses a low fat version (potentially dropping the fat content from 20 grams down to 2 grams), the muffin would still likely contain about 290 to 340 calories. In other words, the low fat, super-sized muffin is still higher in calories than the smaller, full-fat version. (Note that although low-fat muffins are no longer high-fat foods, their high-sugar content — up to eight teaspoons of sugar per muffin – keeps these foods in the energy-dense category.)

Reduced-fat versions of foods that start off as super-rich products can also be misleading. For example, a one-cup portion of conventional vanilla ice cream will cost you roughly 270 calories. Light versions, which trim the fat from 14 grams to 3 to 5 grams, can drop the calories to about 210 for the same portion size. However, decadent gourmet ice creams can contain from 480 to 580 calories per cup of vanilla ice cream. The light version of these products only reduces fat to the level of the conventional “full fat” ice cream. Because sugar content remains high, the 350 to 400 calories in gourmet light ice cream are often substantially higher than the regular version of conventional varieties.

Reduced-fat peanut butter is another example. Although lower in fat than regular peanut butter, with added sugar, starches and/or soy protein, the calories remain the same.

Not to discount all reduced-fat or low fat versions of foods — many do save calories. When purchasing cheese, milk and meat, for example, choosing the lower-fat products means less cholesterol-raising saturated fat and fewer calories. And if you just can’t live with fat-free cheese, even saving 20 calories per ounce with reduced-fat cheese can still be worthwhile.

The bottom line: By substituting a few lower-fat versions for the higher-fat foods you eat frequently, you can save calories, which can add up to make weight control easier. The key is to make those switches without simultaneously doubling your portion size or choosing the “light” version of a product richer than something you would normally choose.

最近一篇关于饮食和癌症的报导建议控制消费高能量食物，这篇报道是由美国癌症研究机构发布的。这个建议主要针对提高控制体重-曾经也在一篇关于癌症的报道里提到过，因为肥胖和癌症之间有着令人信服的联系。

报道中提及的高能量食物主要指卡路里含量高的食物，经常是因为这些食物含高脂肪高碳水化合物和或含附加糖。然而，请注意，有些高能量食物，也就是那些相对未经过加工有大量营养的坚果干果，当作为你健康饮食一部分合理食用时就不能把这些食物和长胖联系起来。

然而，大部分美国人选择其他种类的高能量食物，且研究表明这些食物增加增肥，超重和肥胖的几率。一个很流行的消费者方案就是选择同种食物的降脂或无脂产品。但是这些低脂肪食品并不总是意味低能量，尤其在你摄食比较多的情况下。

在美国食品供应处加大食品尺寸前，一个直径小于三英寸的蓝莓松饼可能含250卡路里能量。然而，今天许多面包店和咖啡店供应的松饼是原来老款式的两倍大，即使消费者选择低脂肪的松饼（脂肪已经从20克降到2克），其能量也可能有290到340卡路里。换句话说，低脂肪超大个的松饼所含的能量要比全脂个小的高。（注：尽管低脂松饼不再属于高脂食物，但是高含糖量使这些食物依旧属于高能量类。

起初作为超级有钱人的降脂版的食物也是一个误导。例如，一杯传统的香草冰激凌含270卡路里，轻脂版从原来14克改为现在的3到5克，同等大小的热量降到了21o卡路里。然而，精致冰激凌每杯含480到580卡路里能量。轻版产品只是将脂肪降到了传统全脂冰激凌的水平。因为糖分含量依然很高，350到400卡路里的精致轻版冰激凌往往比普通传统版的含糖量要高。

降脂花生酱也是一个很好的例子。尽管脂肪比普通的要低，但是附加糖，淀粉，大豆蛋白使能量和原来一样。

不要考虑所有的降脂或低脂食物，许多也能减少能量。例如，当你购买奶酪，牛奶，肉类时，选购低脂产品意味更少胆固醇饱和脂肪和更少的能量。如果你的生活不能缺少无脂奶酪，即使每盎司减少20卡路里，选择那些降脂奶酪，也是值得的。

底线：通过食用低脂版取代你经常食用的高脂食物，你不仅可以减少能量的摄入，也可帮助你更好的控制体重。关键是做好转换，既不会同时增大你选择的量，也不会选择比你平常选择的糖分还要多的轻版产品。