HOME

Dear Lucy: Your answer to the question about basal metabolic rate just raises another question in my mind: Let’s say, just hypothetically, that a woman has been consuming fewer calories than her “total daily energy expenditure,” or TDEE, and still is not losing weight. What should she do? Talk about frustrating!  —T-weedle-DEE

Dear T-weedle-DEE: The situation you describe certainly does sound frustrating! Hypothetically speaking, of course. For an answer to your question, Lucy returned to her source for the previous answer, our MIT Medical nutritionist and calorie guru, Anna Jasonides, R.D., who had several hypotheses that might explain this hypothetical conundrum:

• Underestimating calories consumed: Unfortunately, Jasonides says, a number of research studies have shown actual caloric intake is often much higher than people’s best estimates. “This is usually because people miscalculate portion size,” she explains.
   
• Overestimating calories burned: At the same time people underestimate their caloric intake, Jasonides says, they tend to overestimate the number of calories they are burning through exercise. “Walking 30 minutes three times a week barely makes a dent when it comes to weight loss,” she says. “Government recommendations advise people who want to lose weight to aim for 60–90 minutes of moderate activity every day.”
   
• Calculations don’t work as well at the extremes: “The equations in my previous answer yield the best estimates for people who are close to their ideal weight,” Jasonides clarifies. “If you’re obese, the result is likely to be an overestimate; if you are very thin, the result is probably an underestimate.” For people who fall into one of these categories, Jasonides suggests redoing the calculation using ideal body weight instead of actual weight.
   
• Everyone is different! Finally, Jasonides acknowledges, an individual could be doing everything correctly but still have trouble losing weight because his or her individual metabolism is slower than average. “Equations for estimating basal metabolic rate and caloric burn are based on averages,” Jasonides says. “You may have a different ‘set point,’ which means your body will resist weight loss even when the math says you’re operating at a caloric deficit.”

If you believe you might have a slower-than-average metabolism, it might be helpful to visit an outpatient facility that performs direct measurements of metabolic rate by measuring oxygen consumption. This quick, noninvasive test can provide answers about an individual’s unique metabolism in order to determine an optimal caloric budget for weight loss or maintenance. 

There are also several medical conditions that may hinder efforts to lose weight, Jasonides adds, including insulin resistance and hypothyroidism. In any case, she suggests that an individual who is having trouble losing weight start by consulting a nutritionist for an assessment and, perhaps, a reality check. “A nutritionist can help you figure out if your calculations of caloric intake and expenditure are correct and can offer additional information and suggestions to help you reach your weight-loss goals.” Jasonides says.
 
Lucy hopes her answer to this hypothetical question will be helpful to all the very real people out there who are trying their best to reach a healthier weight. —Lucy

Information contained in Ask Lucy is intended solely for general educational purposes and is not intended as professional medical advice related to individual situations. Always obtain the advice of a qualified healthcare professional if you need medical diagnosis, advice, or treatment. Never disregard medical advice you have received, nor delay getting such advice, because of something you read in this column.