We are gaining weight as a nation. About eighty percent of illnesses are self-induced, with diet contributing heavily to our misery. About seventy-four percent of Americans are currently overweight. Our country spends $147 billion a year to treat obesity, $116 billion to treat diabetes, and hundreds of billions more on cardiovascular disease therapies. The many types of cancer that have been linked to the so-called “Western diet” that accounts for billions more, according to a recent Nature article.
One way to contribute to health and well-being would be to change the way we eat. An on-going problem with our eating habits is that we have grown accustomed to foods which are not nutritious but are easy to prepare and less expensive than healthy foods. Most of us know what we should eat but we need to have the discipline to shop, prepare, and stick to a diet.
Why do we overeat? Undoubtedly, there are many reasons. Food has become entertainment and we often go to a restaurant for the experience as much as the convenience. Socialization—getting together with people to chat—is also very common today. “Meet you for lunch” or “Let’s get together for dinner” are common ways to connect. Finally, I believe we just get in the habit of increasing the size of our portions. We consume ten percent more calories per day than we did in the 1970s, thus adding to the circumference of our waistlines. Both portion and plate sizes have also grown over the decades. Many restaurants entice customers with enormous portions, making us believe we are getting more value—and even two meals!—for our money.
To understand why being overweight is an important health consideration, and to quantify how much we are overweight, we can use measurements which are more sophisticated than just total weight. Typically, “total weight”—as a single measure—has been the gold standard. This measurement is easy to do and great for following progress over time.
Recently, Body Mass Index (BMI) and Waist-Hip Ratios (WHRs) have become more commonly employed. They add value by relating height to weight, as well as provide prognostic value for overall mortality (death rates).
BMI is defined as the ratio of weight-to-height and can be found in many graphs on the internet (http://www.nhlbisupport.com/bmi/). It is useful as a proxy for body fat percentage. BMI is a simple measure of a person’s “thinness” or “fatness,” allowing for populations of people to be compared. Very tall people may have a falsely high BMI which is a flaw in this measurement as the weight is divided by the square of the height. As the height increases, the square becomes progressively larger in the denominator of the fraction, causing the BMI to be erroneously high. Another artifact is in the very muscular athlete whose weight, since muscle is denser than other tissues, results in a “falsely” high weight-per-height ratio.
Having a high BMI can be an indicator for risk of heart disease and other health problems, which is the real “take home” message.
Waist-hip ratios are also important predictors of health status and risk for disease. This metric is also easy to calculate (http://www.bmi-calculator.net/waist-to-hip-ratio-calculator/). Having a larger waist than hip size carries a higher risk than the other way. The former is called “apple shaped” while having bigger hips than waist is called “pear shaped.” There are optimal ratios which are gender specific and can indicate good general health, fertility and susceptibility to disease.
Together, both of these measures, BMI and WHR, add to the fund of knowledge which is readily available to all of us. Participating in health screenings which include these two gauges will help promote, maintain, and restore health.
Being cognizant that “we are what we eat,” will make a difference in so many ways—as individuals, as a community, and as a nation. Let’s eat well but intelligently.
