Weight is a touchy subject, just like food preference and taste in men (or women). But this does not mean a discussion should be avoided, and because your body weight, not to mention your body fat percentage, is such a strong predictor of your health and longevity, it's a good idea to know how much you should tip the scale. What's your ideal? The Metropolitan Life Insurance company came out with a table (most recently in 1999) indicating weights (for various heights and body frames and specific for each gender) at which mortality was lowest. It would seem from this table that one's ideal body mass index is around 23. Met Life never used the word "ideal" but living a long life, in other words not dying prematurely from heart attack, cancer, stroke, and other major killers, would seem like a good thing, we dare say an ideal thing, for most. (You can calculate your own BMI here.)
Now there have been research studies like this one published in JAMA whose conclusion has come to be called the obesity paradox, which hints that being overweight may give some advantage as far as longevity is concerned, but don't be swayed by this finding, which is "complete rubbish," according to Harvard MD Walter Willet, who is head of the department of nutrition at the Harvard School of Public Health.
But like politicians, scientists love to disagree, so let's let the talking heads do what they do best and talk while we avail ourselves of our God-given powers of observation and analysis, which we are born with and despite the efforts of education to take common sense away, still persist into adulthood, at least in most people. So, who to observe?
Athletes are the modern day demigods as far as fitness is concerned. And athletes tend to achieve weights that allow for the best performance in their given sport. Much variance can be found in the "ideal weight." It depends on the sport. Obviously a shot putter, who relies on short bursts of brute strength, will weigh a lot more and have a lot more muscle than a marathon runner, who may look like a walking (or running) skeleton with hardly anything but skin clinging to the bones.
If your goal is to run 26.2 miles, then too much muscle is a liability, as it means more of a load to carry. But life does not call solely for the brute strength of the shot putter nor the sheer stamina of the long distance runner; often it calls for both strength and endurance. Therefore your ideal weight should include enough muscle to add strength while being light enough for you to compete in and excel in the journey that is life.
What sport prepares a person for this journey, and is therefore a metaphor for life? Triathlon is pretty close.
So how much does your average competitive triathlete weigh? We took a look at the top triathletes, male and female, guys like Javier Gomez and Craig Alexander, gals like Anne Haug and Felicity Abram, and we averaged their heights and weights. Here's what we found:
Male triathletes (averaged): 5 feet 11 1/2 inches; 148.5 lbs
Female triathletes (averaged): 5 feet 7 inches; 125 lbs
What's that in BMI? For guys it's 20.4. For women, it's 19.6. Wow, that's low. A normal BMI is 18.5 to 24.9, so triathletes of both sexes fall on the low end of normal, which seems to be the high end for fitness. Variations exist for frame, a few pounds up or down, and triathletes like other athletes are human and can gain 10 or so pounds in the off-season, but the conclusion is pretty simple: if you want to be both strong and fast and cover long distances, the fewer the lbs you pack, the better off you are.
Now you may argue that you are not a triathlete, have no intention of being one, and couldn't sacrifice the 10 or 15 or 20 or more weekly hours which these exceptional individuals devote to training. Your life is sedentary, a succession of switched seats (from the bed to the table, to the car and then to the desk, and back), your longest journey being across the parking lot or up a flight of stairs. That may be your version of real for now, but that shouldn't stop you from striving towards your ideal.
Now we know our definition of ideal says little about longevity. Athletes may perform at their highest level then keel over and die at 50, like the dearly-missed James Gandolfini. We'll leave that for the talking heads to discuss. But if you want to live life at the highest level for as long as your days are granted you, then use this simple formula to calculate your ideal weight and make efforts to stick as close to it as possible.
For men: 100 pounds for the first 5 feet of height, add 5 lbs for every inch above that.
For women: 95 pounds for the first 5 feet of height, add 4 lbs for every inch thereafter.
And if you eat a plant-based diet loaded with sweets, greens, beans, and seeds, you won't have to work out like a maniac. Your body will naturally reach its set point weight.