The old complaint that our metabolism is so slow that we cannot lose, or worse, that we gain weight on very few calories, has resurfaced. The good news is that research (and common sense) has shown that it really has nothing to do with one’s metabolism. We now know that a fit person does not have a faster metabolism than an unfit person. Why is that?
When discussing metabolism, it is necessary to understand the pieces that make up total daily energy expenditure (TDEE), or simply put, how many calories you burn a day. TDEE is determined by your basal metabolic rate (BMR), calories spent processing the food you eat, and your activity level. The first two pieces of the puzzle are pretty standard for people of similar weight and size and not subject to too much manipulation by you. But the activity energy expenditure, how many calories you burn in a day because of how much you move (or don’t move as is often the case) is tremendously variable and the most easily controlled part of the equation. The problem with the metabolism explanation is that metabolic rates between like-size humans with different parents do not vary nearly enough to match the weight gain differences experienced by many chronic dieters. Furthermore, heavier people burn more calories than lighter people when performing the same work. It simply takes more energy to move a heavier weight, no matter what the activity (we will learn to use this to our advantage!). What really confuses the issue is that the vast majority of overweight people dramatically underreport their calorie intake by 35%-60%, and the more overweight we are, the more we underreport. However, almost ALL of us overestimate how much our daily activities, including exercise, contribute to our average daily calorie expenditure.
It is the misjudging of one’s total daily energy expenditure (TDEE) that has recently led to the revival of the slow metabolism claim. If metabolism is defined as the sum total of all metabolic activities in the body over a period of time, such as a day, then there is a certain truth to many people having a “slow metabolism”. Their daily movement and subsequent calorie burning are minute and lower the total number of metabolic activities in a day. It is important to realize, though, that this is due to low activity and movement, not a genetic defect that causes reduced calorie burning in response to increased activity. Most people gaining weight are working both ends of the equation--eating more than they think and moving less. Before we move ahead, let’s review what we just discussed.
1. People of similar weight burn a similar number of calories, no matter where or who you came from
2. The heavier you are, the more calories you burn
3. Underreporting of calories is common
4. Overestimation of activity is common
5. Weight is gained when calories eaten exceed calories burned
6. Weight is lost when calories eaten are less than calories burned
Calorie expenditure estimations are based on old world lifestyles
Once we were able to measure how many calories most people actually burn in a day with new movement monitoring technology, we were shocked. It is hard to imagine that though we are constantly on the go—working, running errands, performing family duties, and even exercising up to 3-5days per week—we burn so few calories.
In modern developed nations, total daily energy expenditure in almost all people, including exercisers, is much less today than what it was in previous years without added exercise. , And it’s far less than formulas predict based on our definition of active. For example, 75 years ago an average person might have burned 3000-4000 calories a day just to live and raise a family, and they NEVER “exercised” or became overweight. To put it into perspective, if you wanted to equal our ancient hunter-gatherer ancestor’s calorie expenditure you would need to ADD “3.5 hrs of running at 9 mph or swimming for 3.7 hrs or 5.7 hrs of walking over fields and small hills”.v And they were not exercising, they were just going through their day. Oh, and they were significantly smaller than we are today (refer to point #2 in the first section). Obviously there have been no changes in the human genome (it takes over 10,000 years for any significant alteration to take place), yet today the average female gains weight on 1600 calories per day and males at 2200--even WITH occasional exercise!
We’ve now discovered that our daily lifestyles burn so few calories that we can’t make up the difference between what we currently expend and what our leaner predecessors burned by simply adding a one-hour workout. The typical American’s daily activity level is 65% of that of our Stone Age relatives and we would need to add a 12 mile walk to our day to approach their energy expenditure levels.v No wonder people feel they have a “slow metabolism”!
Don’t just sit there, move!
Adults commonly report that they’re working out more than ever and eating the same healthy portions but are no longer able to lose weight or maintain weight loss. The simple explanation? It’s not the workout or your metabolism, but as your world changes the rest of your daily activities require fewer calories than in previous years. We humans are a smart lot. As a species we tired of the peril and exhaustion of having to hunt and gather our food. With our big brains and opposable thumbs, we are the only animal that has managed to change our environment. We have created a world where food is plentiful and little physical effort is required to thrive and survive. Yes, as life speeds up, we literally slow down. Most of us sit, often. We sit to drive to work. Sit at a desk. Eat our lunch while seated. Return to our desk to sit some more. When the work day is done we get in the car, sit and go home; or if we are really proactive, to the gym. In the gym we sit on the bike and peddle. Sit in the chest, back, shoulder, arm and leg machines. Get in the car, go home and sit in front of the TV. Whether it’s your job requiring more sit-down time, you live or work in a smaller area, or you no longer do your own house or garden work, wash your car, chase your siblings (or spouse) around the house, have to get out of your car to buy food, prepare home cooked meals – or like most adults/parents you find yourself having to quickly get from place to place and this requires more time sitting in cars – at some point you are on average simply moving less.
Children at least have more opportunities to move than adults, which is why there are significantly fewer overweight children than adults. The average child takes over 12,000 steps daily while the average adult takes fewer than 6,000. And children don’t have to drive, they can fight in the back seat, and then get out of the car to attend their activities and they still enjoy running around anywhere just because they can. Anyway, you get the point – it’s not your metabolism –it’s the ever-faster but inactive days of our lives. The simpler solution here is to move as much and as often as possible. Every little bit of movement adds up. In fact, increased daily movement can help you accumulate a total calorie burn equal to or even greater than that hour gym workout!
Exercise does not undo poor eating
Adding a one-hour intense workout to anyone’s day only increases their calories burned that day by about 200-400 (depending on your size). Compare that number to a typical coffee drink or fast food burger (500 calories or more). A typical exerciser burns 200-300 calories during 30 minutes of cardio. How long do you suppose it takes to eat 200-300 calories? A minute? Five minutes? There is simply not enough time in the day to undo all of the poor eating moments that exist. To make matters worse, life has gotten so busy that we don’t have time to walk to our destinations even if we wanted to – hence, as described above, “we have to hurry up to sit somewhere else.” So do the math: if we participate in intense one-hour workouts four times weekly, we would be active four hours/wk, and unless you have a job that requires hard labor, most of us would be considered basically sedentary for the remaining 164 hours. And don’t look for the things we discussed here to change anytime soon if you plan on raising a family and making a living. In fact, I would argue that life will become more and more sedentary as the world demands faster information through the use of technology. In summary, most of us do not or cannot move enough each day in order to be able to eat what we feel we should, or anywhere close to the number of calories our earlier generations consumed, without gaining weight. So what can we do besides blame our metabolism?
Time to change the way we view and do things
Old eating styles do not always apply well to modern society and a busy lifestyle. The old “three squares” is just not realistic for many. Our eating strategies must evolve to fit into the new world, which means breaking with outdated parental advice, like eat everything on your plate. And, statistically speaking, for many Americans at least half of the calories eaten are now acquired through portion-crazy restaurants. It is next to impossible to accurately estimate the true caloric content of these meals– even if it’s printed on the menu!
Our bodies can no longer “automatically” burn the number of calories we consume, making it more difficult to maintain a small waistline or proper health. This means, to some degree, we need to count calories until we’ve “re-wired” our brains to be able to identify how much food we need to consume in order to look the way we want.
It is well-documented that successful dieters, celebrities and most athletes consume four or more “meals” a day by consistently using healthy snacks such as meal replacement drinks (MRD), bars or other sources of controlled calories in their daily food planning. Frozen dinners and other portion controlled meals have come a long way since the mystery meat of the 70’s and can offer a tasty and healthy option to ensure appropriate caloric intake.
Shrink portion sizes and increase meal frequency
The goal is to manage hunger (meal frequency) and make up for the inability to move as much as our free-eating predecessors. Think four to six feedings a day depending on your caloric allotment. If you’re allowed fewer than 2000 calories a day, eat something substantial no less than four times daily, with up to two “meals” being healthy dotFIT snacks. If you’re allowed more than 2000 calories, you should have no less than five “meals” including up to three dotFIT snacks. If we plan on reversing the current weight gain epidemic, it won’t happen without a departure from our current approach to eating. Our lifestyle changes have outpaced our body’s ability to evolve our eating habits that would otherwise naturally control our caloric intake in order to maintain health. Working healthy snacks or meal substitutes into our daily food plan in order to control portions and accurately determine calories is an important step in helping us manage our daily food intake so that we stay fit while earning a living in 21st century.
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