Your body mass index, or BMI, is a measure of your body fat based on your height and weight, according to the National Heart, Lung and Blood Institute. In order to be at an ideal weight, you must have a BMI of 18.5 to 24.9. A BMI of 25 to 29.9 is considered overweight, and below 18.5 is considered underweight.
Body Mass Index
A 5-foot, 10-inch male should weigh between 129 to 173 lbs. to have a BMI of 18.5 to 24.9. Weighing less than 129 pounds at 5 feet 10 inches tall classifies you as underweight, putting you at risk for osteoporosis, trouble maintaining body temperature and difficulty fighting off infection, according to Medical News Today. Being overweight, weighing more than 173 lbs., also has risks. People who are overweight are more likely to develop Type 2 diabetes, heart disease and certain cancers.
If you're 5 feet 10 inches tall and weigh just a few pounds over your ideal weight, such as 178 lbs., you may think those few extra pounds aren't that big of a deal. On the contrary, according to the New England Health Advisory, an extra 10 lbs. can add up to 60 lbs. of force on your knee joints with each step you take.
In a 2008 issue of Today's Dietician, the Helen F. Graham Cancer Center in Wilmington, Delaware reported that between 8 percent and 9 percent of the population is underweight. Though weighing too little may seem preferable to weighing too much, the health risks of being underweight are just as severe. Underweight people are prone to low muscle mass, hair loss and fluctuating hormone levels.
There is one glitch to the BMI scale, according to Katherine Zeratsky, R.D., of the Mayo Clinic. You may weigh a normal amount but can still have so much body fat that you qualify as obese. For example, if you're a man who's 5 feet 10 inches tall, and you weigh 160 lbs., your BMI is 23, which is normal. However, if you have 40 lbs. of body fat, you would have normal weight obesity. If you're a male with a toned, athletic build, according to the American Council on Exercise, your body fat ranges from 6 percent to 13 percent. If you're fit, a step below athletic, your body fat ranges from 14 percent to 17 percent. Only if your body fat is above 25 percent are you considered normal weight obese.