Why You Won’t Lose 95lbs by September

While reading Fran’s fitness blog, I started to think about why counting calories doesn’t work as well as it should. Even with a diet diary, tracking calories, carbohydrates, fats, and fibre is not as scientific as it should be. One problem is the serving sizes on the label don’t necessarily correspond to what we actually eat. For example, my breakfast cereal serving size is “1 cup cereal with 1/2 cup skim milk.” Like almost everyone else, I don’t measure, I just fill up the bowl. Today, I measured and found I was using 1 1/4 C cereal and 10 oz (versus 4 oz) of milk. The 1/4 C extra cereal is 47 calories. The extra milk, 90 calories. Those 137 extra calories could add an extra 14 pounds per year:

137 calories/day * 365 days / 3500 calories/pound = 14.3 pounds


1 pound fat * 453.6 grams/pound * 9 calories/gram fat = 4082 calories
10% of the fat content is water: 0.9 * 4082 = 3,674 calories
5% of this “passes through”: 0.95 * 3,674 calories = 3,490 calories.
For ease of math, we’ll round it to 3,500 calories.

Apparently this is pretty common. According to the Washington Post (Lean Plate Club by Sally Squires, free Registration Required), studies show people understimate what they eat by 40%.
We all know weight loss occurs when there’s a caloric deficit, while weight gain occurs when there is a surplus. The formula is simple:

Weight loss (lbs) = (calories burned – calories consumed) / 3500

Suppose there’s a relatively sedentary male acquaintance of ours. We’ll call him
Dude likes easy math, so today, Dude is 5′ 10″, and 240 pounds, making his basal metabolic rate (BMR), the amount of food necessary to maintain normal body function and steady weight, 2,000 calories a day.
Let’s assume Dude wants to lose 20 pounds.

For the first calculation, Dude wants to lose weight without exercising and latches onto the Starvation Diet, which apparently involves sewing your lips shut. With a 2,000 calorie-a-day deficit, it would take Dude about 35 days to drop those 20 pounds:

20 lbs * 3,500 calories / lb = 70,000 calories
70,000 calories / 2,000 calories/day = 35 days

35 days. Well, Dude, it’s probably worse. First, the BMR would decrease as Dude loses weight. (For example, at 220 lbs, the BMR is 1,938 calories.) Second, this dude’s body would go into survival mode, and start reducing body function, further decreasing the BMR. Finally, we’ve ignored the boomerang effect that would occur when Dude goes off the diet.

For the second calculation, suppose Dude just can’t give up his Cream Cheese Brownies. He insists on keeping his 2,000 calorie diet the same, but he promises to exercise it off. Here are some of his options:

  1. Bowling — it’s not the most taxing sport, however. For example, one game consumes about 50 calories. Dude has to bowl 1,400 games! During this time, one of his arms becomes noticably larger than the other.
  2. Ride a bike — if Dude rode a bike at 12mph, he could expect to burn 871 calories an hour. Better, but it would still take 80 hours of non-stop cycling, without eating, to lose 20 pounds. Not eating is going to be a serious problem since
    the body stores about 2,000 calories in glycogen. In theory, Dude can bike at a slow enough rate such that he’s burning mostly fat for calories, but this just increases the time in the saddle. (For comparison, during 7 1/2 hours of biking Flying Wheels, I burned about 5k calories, but I consumed at least 3,500 calories in the process.)
  3. Running — let’s suppose Dude runs a marathon at a 10-minute mile pace, or 1,089 calories an hour. Over the course of the marathon, he’d burn up 4,755 calories. 15 marathons ought to do it…. except the very few people who can bang out 15 marathons aren’t the same ones who have to lose 20 lbs. (Dude will still have the same glycogen limitation with cycling.)

These examples are deliberate: reducing eating helps, exercise helps, but neither will work as well on its own. I suppose that it is for this reason eBay is so profitable as people seek a quick fix.

If you go to eBay’s home page, you’ll notice that at any given time, their “featured auctions” include at least one “Lose 95 lbs” auction. I just checked, and there are three. eBay makes a lot of money off these high-churn, snake-oil salescreatures. It rewards them with metallic Power Seller status and a special icon that implicitly conveys some kind of credibility.

Thing is, all these auctions read the same (see buff female,
pumped male). The ingredients are all claimed to be safe, effective, cheap, delivered quick shipping, etc; the implied human testimonials shown have not only lost weight, but they are also tanned, their vision has mysteriously improved such that they no longer need glasses, boobs/pecs are more pendulous, abdomens have the “six pack” look, and butts are tighter. Because these are obviously amazing pills, the auctioneer has typically hit the 1,000 “feedback” mark. If you actually read the “feedback,” you’ll notice that it is based primarily on the auctioner’s ability to place the pills in the mail and have them arrive. Efficiacy is rarely mentioned.

For the third calculation, Dude goes on the Deluxe eBay All-star Diet (D.E.A.D.). He buys these magic sugar pills, but doesn’t modify his diet or exercise habits.

The fine print of these ads suggests 12 pounds a week is a typical amount of weight loss. To put this in perspective, this is saying that Dude, on a 2,000 calorie diet, is effectively consuming minus 42,000 calories during that period. The pills defy physiological logic by creating minus 56,000 calories:

The basic truth:
Weight loss (lbs) = (calories burned – calories consumed) / 3500
Rearranging the equation:
Calories Burned – Calories Consumed = Weight loss (lbs)* 3500
Calories Burned – Calories Consumed = 12 pounds * 3,500 calories / pound
Calories Burned = 42,000 + Calories Consumed
= 42,000 + 2,000 calories/day * 7 days
= 42,000 + 14,000
= 56,000 calories

Think about it for a moment. The claim is that the pills negate the 2,000 calories Dude consumes and speed up Dude’s metabolism 3x. Without any side effects. Conclusion: the pills cannot possibly work. Most likely: Dude would be out at least $14, is slightly dehydrated from extra water loss, and has already left his eBay feedback for “quick shipping.” He’s also too embarrassed to admit he’s such a doofus for believing the advertisement, or he’s afraid of retributive negative feedback. The worst case is the pills do something irreparable to Dude’s body like shutting down his renal function, destroying his liver, or giving him a heart attack. (Death is guaranteed easy weight loss.)

What should Dude do? Make a permanent life change to eat less, exercise more, and skip the pills. If Dude can create a relative deficit of 600 calories a day, he’ll lose 15-20 pounds in about six months. Here’s how he might create that deficit:

Eating less: Dude can cut out 180 calories by drinking one fewer sugared soda a day. (Dude, try plain carbonated water. Just don’t substitute a venti Starbucks Mocha with whipped cream — that will add 490 calories.) If Dude switches from Whole milk to 1%, he’ll save another 50 calories. For good measure, Dude also passes on the french fries, opting for a fruit salad.
Exercise: If Dude walks his dog for an hour, he’ll consume 375 calories.

Another suggestion is to maintain a diet diary. Even though it’s hard to accurately measure portions and correlate them to calories, fat, carbos and fibre, the mere act of writing things down every time you eat will provide useful insight. In my case, it was useful to see how often I snack: a handful of tortilla chips here, ten chocolate chips there, some crackers — it all adds up.

There are also support groups such as Weight Watchers who have had a good track record of success. One of the most graphic examples I’ve seen was a woman who showed a group what one pound of fat physically looked like.

Two columnists I can recommend are The Wall Street Journal’s Tara Parker-Pope, and the Washington Post’s Sally Squires. Both have thoughtful columns on food and nutrition.


  1. Great article. I found it really interesting.

    I would only add a psycological aspect of losing weight, specifically the *desire* to do so. Sure we all sorta want to lose a few pounds and will cut a brownie here or a coke there, work out a few times before losing interest, but the fact of the matter is that for most of us, the S.O. isn’t going to leave us due to the extra luv handles, so there is little incentive.

  2. Jim – I think this is a great article, but would add one item possibly overlooked.

    Each additional pound of muscle burns about 40 calories a day. Using your calculation would imply that an additional 12.5 pounds of muscle would burn about a pound of fat a week (if everything else remained the same). It would take 5 months to drop 20 pounds this way …but probably twice as fast if you were working out an hour a day.

    Generally I agree that it is about lifestyle and priorities though. Middle age generally puts job, family and a myriad of other things higher on the list than exercise. And if you are in hi-tech your priorities are often: job, job, job, family, sleep.

    One final note though …when there is a true weight loss pill created …and there will …it is unlikely that Gates or Buffett will remain the richest men in the world …and eBay will have to coin a new term, such as “Extra Super Duper Power Seller.”

  3. The MBR calculation makes some gross simplifications about the body composition that I don’t think are unreasonable because it would be much harder to gain 12.5 pounds of muscle mass than it would be to lose 12.5 pounds of fat. (And really, if my body were a greater percentage of muscle, I wouldn’t be concerned about losing weight, would I 🙂

    When I had my VO2 measured last year, they did a MBR calculation based on my carbon dioxide output while I was at rest. (There’s apparently an archaic book reference one can use to look this up, too.) I was surprised how low my MBR was — if I was on a 2,000 calorie diet, without any exercise, I would likely gain weight.

  4. From my viewpoint, what I really needed to do was to stop looking at nutrition, good nutrition, as a punishment and come to senses. The real punishment was feeling bad about myself for being overweight. It became simple to replace the brownie or spoonfull of peanut butter when I stopped looking at it as giving something up and began to see all I had to gain…..which wasn’t pounds!

    Although mirrors are good at getting perspective, photos are far superior :o)

  5. hey sup hows it going i am way over weight i really wanna lose weight i am 12 and i weigh 195 it sux i really wanna lose weight this sucks because everyone is school makes fun of me and even when i wear a one peice of a swimming suit i feel fat i wish i could wear a 2 peice but i cant please help me

  6. Hey Melissa: if you’re 12 and you really want to lose weight, one of the best things you can do is ride a bike. Ride to school, ride to your piano lesson, ride to the mall. Even if you don’t lose the weight, you’ve got several benefits:

    a. you’ll be in better shape, even if you do stay fat
    b. you’ll get away from those idiot “other kids” who are making fun of you. I spent too much of my time at age 12 and 13 being tortured by others. May the fleas of 1000 camels infest these kids’ armpits.
    c. you’ll be free and independent. Who needs mom to schlep you around in the mini-van when you’ve got your own wheels?
    d. when you finally get your driver’s licence in a few years, you’ll be ahead of the game — you’ll know the rules of the road better, be able to judge traffic better, and so on.

    The other thing for you to do, Melissa, is to stay off the junk food. Don’t drink soda pop (even diet), don’t eat potato chips or french fries, stay away from sweets.

    My 12 year old is going to do STP — 200 miles from Seattle to Portland — with me in a few weeks. She started this spring with a 15 mile ride down the trail being a big ride for her. She’s slowly ramped it up since then with regular riding. She is “bad at gym” and all the other kids know she can’t kick a ball or catch one to save herself. But she’s gotten in great shape from cycling. I know you can do it too!

  7. For those males approaching 50 and older … I highly recommend the book “Youger Next Year” by Chris Crowley and Henry Lodge … if this does not motivate you to change your lifestyle then nothing will.

    Go luck.

    p.s., Claire, I love the 1000 fleas …

  8. thanks for the recommendation, paul.

    melissa: weight loss is all about the balance equation: eat less, exercise more. as claire noted, biking is excellent exercise. you can do it by yourself, at your own pace, seeing the world in the process.

    there are also lots of opportunities for removing empty calories from the diet. sweetened beverages is one of the easiest to cut out.

  9. you didn’t calculate the calories needed to maintain everybody functions. if dude doesn’t eat at all and doesn’t exercise at all either, he will still lose weight. if 2000 calories is what he needed to MAINTAIN his current body weight, that is -2000 calories every day if he doesn’t eat. in 35 days, without using abstract calculus formulas, that is 70,000 calories lost on its own. dude would lose close to 40 lbs in 35 days if he exercised without eating (which is impossible). this is only one of your fallacies–there are more.

  10. you didn’t calculate the calories needed to maintain everybody functions.

    Perhaps you missed the first example:

    For the first calculation, Dude wants to lose weight without exercising and latches onto the Starvation Diet, which apparently involves sewing your lips shut. With a 2,000 calorie-a-day deficit, it would take Dude about 35 days to drop those 20 pounds:
    20 lbs * 3,500 calories / lb = 70,000 calories
    70,000 calories / 2,000 calories/day = 35 days
    35 days. Well, Dude, it’s probably worse. First, the BMR would decrease as Dude loses weight. (For example, at 220 lbs, the BMR is 1,938 calories.) Second, this dude’s body would go into survival mode, and start reducing body function, further decreasing the BMR. Finally, we’ve ignored the boomerang effect that would occur when Dude goes off the diet.

  11. I enjoyed this article very much Jim. It is a good explanation as to why fad diets just do not work. I believe that exercise is the key, to which cravings for the sweet and sugary snacks will decrease.

    Now I need to put down the m&m’s because finishing off the bag now seems wrong….

  12. A great site to track calories consumed and burned, along with fat, carbs, sugars, proteins, vitamins, cholesterol, etc. is http://www.fitday.com. It also tracks exercise, basic metabolism, etc., and you can view it all graphically. Once you start putting in ALL of the food you actually eat in a day (and measure it out like Jim’s cearal bowl, instead of just guessing), you’ll be surprised and realize how much you actually eat, and then you can begin to realistically eat a sensible diet to stay fit. Knowledge is power.

  13. Have your Gall Bladder removed, it works wonders. I have lost 38 pounds in 6 months, but can’t get to far from the bath room. Prior to having the gall bladder removed I decided to loss some weight. Did a little math and found I was getting 1,200 cals./day just from the sugar in my Ice Tea. Stopped using sugar in the tea and lost 68 pounds in 6 months. I am able to maintain that loss with no problem. A minor change can make a big difference.

  14. I was 150 pounds 2 weeks ago started going tio the gym mond tuesday and wednesday 15 minutes on the cross country ski machine then 3 sets of 15 on 3 diff arm machines then 3 sets of 15 on leg machines 3 diff ones as well Im burning the pounds off. I dring 1 or 2 coffes in the day with lots of cream no sugar ever in the cofee 1 chocolate bar when I feel like one and salad with oignons and garlic salad olive oil salt and peper drink 3 botles of water per day and pasta once in a while for soper b4 the gym anybody that is over weigh has a life style that is supporting it. If you are really tired of finding yourself ugly fat and really want to drop those pounds you will do it if you dont really want to are dont have sufficient motivation then just stay the way you are and stop complaining! being fat is the gretest thing since its reversable when your really tired of being fat work out push yourself and think of how everyone will admire you your body is a temple treat it accordingly eat pois chiche thats full of proteein that will nourish your muscles i also take vitamines b6 and b12 helps eliminate fat from your metabolisim youll find for almost nothing at the pharmacy good luck and start moving! and dont be afraid to use the muscle machines after cardio it build muscle and muscle burns fat plus youll notice your heart rate stays up wile muscle building i feel great and look great i have another 15 poounds to reach my goal and i feel so beautifull its the best gift i could have given to myself I people look at me and already find i look great ill be the the beautifull girl in a blue bikini you wont be able to keep your eyes off at the beach this summer hope this motivated all of you that want to loose weight

  15. I am trying to lose 50 pounds. I recently had breast cancer and am now cancer free. I work in an office and sit at a desk. My work day is pretty long since I get up at 6:00 a.m. and don’t get home until 6:00 p.m. I eat breakfast every day (1 bowl of oatmeal)and drink a glass of orange juice with my vitamins. I do not get enough exercise and hope to change that aspect of my life. Hope to hear from somone who can give me some encouragement.

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