My Yellow Road to Healthy Weight

Should I eat this piece of cake or not? I will certainly enjoy it very much. What harm will it do? Will this piece increase my weight? Maybe not. The next piece might, but this particular one looks harmless. Even if my weight increases by half a pound, it could be muscle weight. Yes, it probably would be due to muscle weight: I just went out of my house to throw away my garbage and this has to count as exercise.

Do you see the problem? Eating the cake provides an immediate reward, but the punishment is vague and in the far distant future. That is why I got excited when my son Alexey sent me the link to Beeminder, a company that creates an artificial non-vague and not far-in-the-future punishment for eating that piece of cake.

Here is how it works. You give them your target number — in my case my desired weight, but it could be any measurable goal — and the date by which you want to hit it. They draw a yellow path on a weight chart. You must weigh yourself every day. Whenever your weight is above your path, you have to pay real money to the company. Five dollars!

This is a great idea. Suddenly that piece of cake looks threatening. The only problem with using their system is that I have no clue how to lose weight. The company doesn’t provide tools to lose weight: it just provides a commitment device. So it is difficult to stick with the weight-loss commitment without having a proven weight-loss plan.

The truth is that my son sent me the link, I laughed, and forgot about it. Besides, if I ever want to pay money for failing in my commitments, I would rather choose the beneficiary myself. Then I realized that I can use the yellow-road idea to try to lose weight while figuring out what works for me. I call my new plan the Adaptive Diet.

Starting from my actual weight on Day One, I drew a line that represents my target weight, assuming a daily decrease of 0.1 pounds. A deviation of one pound from my target weight on my daily weigh-in is what I call my Yellow Zone. When I am in the Yellow, I continue doing what I was doing before: trying to build new, healthier habits.

If I am more than one pound below my target weight, then I have entered what I call the Green Zone. When I am in the Green, I can allow myself to indulge my cravings. However, when I am one pound above my target weight, I call that the dreaded Red Zone. This Zone has different shades of red. If I am between 1 and 2 pounds above my target weight, I have to eat only apples after 8:00pm. If I am 2 to 3 pounds above my target weight, only-apples time starts at 6:00pm. And so on. Every extra pound above my target weight moves the cut-off time by two hours. That means that if I am 7 pounds above my target weight, I would have to eat apples all day long.

The system has to work: I do not like apples.



  1. Fergal Daly:

    Please don’t be offended but I can’t tell if you are joking or not because I cannot imagine this system working well (which is why I thought it may be tongue in cheek).

    You should have a look at some control theory and delayed feedback. It sounds like you are setting yourself up for hysteresis

    where you repeatedly over and undershoot your target which is going to be no fun at all (and most likely will result in abandoning the system entirely).

    Any system involving self-flagellation and going against your nature is going to be extremely hard to stick to.

    I don’t have a better suggestion as I have never tried to lose weight. Nor do I read a lot of self-help stuff but I do read a blogger who reads a lot. The topic is learning Japanese but it’s somewhat relevant because the techniques are all about how to become good at Japanese without sitting down and suffering (in boring classes, with boring text books etc).

    He talks a lot about motivation, turning things into games, working _with_ your nature instead of against it and how any system that involves pain will cause bingeing and purgeing (I didn’t study for weeks -> I must study all day today -> that was awful, I hate Japanese -> I won’t study again for weeks).

    I bet these techniques have already been adapted to diet, they might be worth trying.

  2. Karthik:

    Weight loss comes down to the fundamentals: calories in vs. calories out. People recommend all kinds of diets, but those are not sustainable in the long term.

    Here’s the best solution that’s always worked for me:

    1. Calculate what your TDEE is (total daily energy expenditure) in calories
    2. To lose 1 lb/ eat 500 calories less/day (~3500 calories = 1 lb)
    2. Choose a good breakdown of protein/fat/carbs based on your workout regimen (I’d recommend 35% protein, 35% carbs, and 30% fat – up the protein if you’re working out more)
    3. Track your food regularly – I use LiveStrong; others use MyFitnessPal. Make sure you come under your TDEE-500 on a daily basis!
    4. If you go over your calories, burn them (walking, running, hiking – whatever your preference may be)

    That is it. Now, working out regularly obviously has benefits, but even so, as long as you eat below your TDEE, you will lose weight. If eating 500 less/day is too hard, then you can start a little high at 250 less/day, and work your way up. But ultimately, your body cannot violate the laws of thermodynamics: you cannot gain more weight than the calories you are putting in – the only times you’ll see “bumps” are when you consume excess carbs or salt/sodium, from water retention. But those will quickly pass.

    So, calculate your TDEE, track your food, and work out ~3 times a week. As long as you do that, you should see those lbs dropping. Good luck!

  3. Daniel Reeves:

    Wow, thank you so much for this wonderful write-up, Tanya! What you call the Adaptive Diet is in some ways a reinvention of The Hacker’s Diet, which Beeminder tries to incorporate the principles of.

    To address Fergal’s concern, Beeminder works jaw-droppingly well but only for a certain personality type, which I think Tanya clearly is and you are probably not. Hysteresis does not seem to be a problem in practice with Beeminder. We’ve put a ton of thought into the algorithms behind the width of the yellow brick road (what Tanya’s calling the green/red/etc zones).

    Your other concern, Fergal, about binging and purging, so to speak, is astute. But that’s part of the genius of the yellow brick road: to force yourself to spread out the effort more evenly. If you can turn it into a game where you don’t have to force yourself at all, that’s wonderful. We think of Beeminder, though, as kind of like the nuclear option when all else fails.

    More on the philosophy behind all this:

    Thanks again, Tanya, for the vote of confidence in this approach! Eager to see how it works for you. You should link to your Beeminder graph here!

  4. Count Iblis:

    “The problem is that according to our current understanding, the number of fat cells can only be increased, never decreased. This means that any new fat cells produced as a result of (prolonged) overeating will always stay with you. What’s worse, as the purpose of fat cells is precisely to store energy, the body will now send more signals of hunger to your brain to keep those fat cells filled up. Obviously this makes following diets that rely only on cutting back on calories very difficult.”

    So, as soon as you’ve reached your target weight and start to eat normally again, your empty fat cells will refill and you’ll soon be back to square one.

  5. andyclark:

    Excellent Math metaphor, thank you. Other introduced diet concepts so.. I feel awkward quoting Dr. Oz or even admitting I accidentally watched a show but… he said that getting fairly vigorous exercise within one hour of waking up helps in all ways from diet to sleeping well the next night. It could be the Hawthorne Effect in action but it is working better than I thought it would.

  6. Beeminder Buzz: Front Page of the Wall Street Journal | Beeminder Blog:

    […] an awesome writeup of lots of Beeminder goals, a testimonial on Reddit, a post by a mathematician talking about the principles behind Beeminder’s yellow brick road, Muflax’s blog uses a thumbnail of his Beeminder graph as an ETA to next blog post, Beeminder […]

  7. rasim:

    hi i have a question can you help me The numbers 1,2,3….2013 are written on 2013 stones weighing 1,2,3…2013 grams such that each number is used exactly once. We have a two-pan balance that shows the difference between the weights at the left and the right pans. No matter how the numbers are written, if it is possible to determine in k weighings whether the weight of each stone is equal to the number that is written on the stone, what is the least possible value of k?

  8. Tanya Khovanova:


    Our paper on the subject is available at:

  9. Tanya Khovanova’s Math Blog » Blog Archive » I’ve Lost 10 Pounds:

    […] started my Yellow Road plan on February 9 when I was 245.2 […]

  10. Tanya Khovanova’s Math Blog » Blog Archive » Ode to My Digital Scale:

    […] new scale prevents inaction. It also allowed me to design my new plan: my Yellow Road. In this plan, my target weight decreases by 0.1 pounds per day. My behavior depends on my real […]

  11. Tanya Khovanova’s Math Blog » Blog Archive » Lost a Digit in Kilos:

    […] friends have started to notice. The chubbier ones ask me to tell them about my Yellow Road. And I don’t actually know what to reply, because the Yellow Road is not a solution. I took […]

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    […] stopped losing weight. My Yellow Road plan stopped working. If you recall I draw a line on the weight/time plane which I call my target […]

  13. Tanya Khovanova’s Math Blog » Blog Archive » My New Yellow Road:

    […] started my Yellow Road a year ago on February 9, 2013, when my weight was 245.2 pounds. My system worked for eight months. […]