How I Lost 20 Pounds in 20 Weeks With My iPhone (or: Data is King)

Well, it was really more like 17 weeks, but who’s counting. ;) First, I’ll give the punchline.


Chad, you were skinny! Why diet?

  • High school: 140 pounds
  • College: 150 pounds
  • Grad school: 160 pounds
  • After four years at IMVU in delicious downtown Palo Alto: 180 pounds

At my height, 180 lbs. isn’t terrible, but the trajectory is obviously wrong. Without adjustments to my lifestyle, you can see what would happen. So I started paying attention.

In February, Laura and I got iPhones. Shortly after, I discovered Lose It!, a calorie-counting and weight-tracking app. I knew my eat-box-of-cheez-its-when-bored habit was bad, so I began simply tracking calories with Lose It!, hoping to break some bad habits. After all, if you give an engineer some data, he’ll optimize it.

A few weeks later, I ended up reading The Hacker’s Diet. It’s a quick, educational, and inspirational read. John Walker’s thesis is that anyone can lose weight if they correct the flawed feedback mechanisms causing them to eat more than they consume every day.

See, our bodies are complicated machines. We can’t entirely understand them, so we use models (created by people smarter than me) to help us predict how our bodies will behave under various inputs. Thus, there are tons of weight loss plans, and I’m sure they’ve all worked for someone: all raw, low-carb, no-carb, low-calorie, intense exercise, glass of red wine every night, protein shakes in the morning, seven snacks a day, etc. etc.

All of that is too complicated for me, so I chose the simplest model I knew: Calories In, Calories Out. It goes something like this:

The Hacker’s Diet (Theory)

(I am not an expert! This is what worked for me. Consult your nutritionist and physician. Don’t starve yourself. Take your vitamins. Etc.)

1 lb. of body fat = 3500 calories
Calories stored = calories eaten - calories burned
Every day, I eat X calories
Every day, I burn ~2500 calories

If X > 2500, you will gain weight at (X-2500)/3500 pounds per day. If X < 2500, you will lose weight at (2500-X)/3500 pounds per day.

Thus, if you eat 500 calories less than you burn every day, you will lose one pound per week.

Key insight: this is not difficult! For example, a strawberry milkshake from In-n-Out is 700 calories. A 6 oz. frozen yogurt with strawberries and mangos from Fraiche is 200 calories. That’s 500 calories saved right there!


Sounds great! How do I deal with this on a day-to-day basis?

The Hacker’s Diet (Practice)

My mother once told me “Chad, be very careful with drugs and alcohol. You have an obsessive personality.” She was absolutely right about the obsessive personality; fortunately, I’ve learned to channel my obsessions productively. (Although I did spend a year and hundreds of dollars on Travian…)

Here’s how calorie-counting with Lose It! works in practice:

  1. Keep track of everything you eat. This is pretty easy because their database contains most common foods. If it’s not in the database, just enter it yourself. Record it right before or after you eat so you don’t forget.
  2. Estimate your daily caloric burn. There are standard estimation formulae, but the exact amount doesn’t matter a great deal. If you are losing weight faster than you expected, increase your burn. If you are losing weight slower than you expected, decrease your burn. I started at 2500 calories/day, but shortly realized my actual burn was 2300 calories/day.
  3. Stay within your daily calorie budget! Treat it as a hard limit so that, if you screw up and eat a Double Double and Shake (1400 calories total) for lunch, you’ll be very sad at dinner when you can’t eat anything else. :( You won’t make that mistake again. *cough*
  4. Drink water. Take vitamins. Sleep. Take care of yourself if you get sick.
  5. Weigh yourself every day. Watch the mostly-linear progress!

That’s all there is to it! Time + calorie deficit = easy weight loss!

Really? Surely there’s more to it…

Unexpected Side Effects

  1. The first couple weeks after I reduced my caloric intake to ~1800, I got hungry. Then tired. REALLY TIRED. I started sleeping 10 hours a night. It turns out that your body is good at noticing “Hey, where’d the energy go? Time to slow the engine down.” I suspect this is the part where most people quit, especially if they don’t see immediate progress. Remember: this effect is annoying, but temporary. Your body will adjust to the reduced intake and before you know it you’ll feel great again.
  2. My headaches are GONE! I used to get very frequent headaches related to low blood sugar. Maybe burning fat means I have a more even supply of energy through the day? Maybe eating less means my blood sugar doesn’t spike? Who knows, but I’ll take it!
  3. Body fat is an inert material. For years, it quietly stores all kinds of chemicals and toxins. Burning fat means those chemicals go into your bloodstream. Some of those chemicals reek. Thus, you will randomly smell like holy hell for a week or so. You can’t predict when either. I thought John Walker was exaggerating… but it’s true:

    As your body chemistry adjusts, other curious things may happen. One day, trapped in a tedious meeting, I began to emit an odor evocative of a roadkill skunk marinated in ratpiss. My esteemed colleagues were either too polite to remark upon this phenomenon, or (more likely) unsure of the culprit, so I managed to escape to the open air unfingered as the malodorous miscreant. This situation persisted for about two weeks, after which it disappeared for good as suddenly as its onset.

  4. Optimizing for fullness per calorie has unexpected effects. Pizza is actually low-calorie when you consider that two slices of pepperoni is only 600 calories and filling. Fruit is also great: 100 calories for a pear.
  5. Alcohol is full of calories. 80 for a shot of whiskey. :x Turns out I’d rather eat some bread than have a beer.
  6. It’s way too easy to blow your budget on soda and juice. Switch to diet soda, iced tea, black coffee, and water. Liquid calories aren’t worth it.
  7. Speaking of, caffeine is awesome. Suppresses appetite and gives you energy.
  8. Body weight is noisy. On any given day, you may be 4 pounds heavier or lighter than the day before. (You can try this at home: drink two bottles of water before weighing yourself.) Some weeks, it will look like you’ve made no progress. It’s infuriating, but hang in there. In the end, your weight graph will be linear.
  9. When it comes to nutrition, everyone’s an expert. “Are you exercising?” No. “Are you eating healthy food?” Do pizza, burritos, and frozen White Castle count? Dieting is hard enough by itself. Actively avoid being too ambitious. It’s much easier to cut calories if you can still eat things you love. Worry about the low-order bits after you hit your target weight.
  10. I used to love the feeling of a full stomach. Now it’s unpleasant. I’ve finally defeated that post-great-depression “EAT EVERYTHING ON YOUR PLATE OR YOU’RE GROUNDED!” instinct.

Getting Through Rough Days

Let’s face it. Some days you’ll screw up and eat too much for breakfast or lunch. At 11:00 p.m. you can’t sleep because you’re too hungry. How do you take the edge off without blowing your calorie budget?

  • Tomatoes. 35 calories PER! If you like ’em, chow down.
  • Cantaloupe. 35 calories per 1/8 melon.
  • Hot chicken broth in a mug. Warm, tasty, and 50 calories.
  • Strawberries. 8 calories per delicious berry!
  • Low-calorie yogurt. 60 calories.
  • String cheese. 70 calories.
  • Pickles. ZERO.
  • Water. ZERO. Somehow, drinking water can make you less hungry!
  • Also, if you still want crackers or cookies, 100 calorie packs are pretty common these days.

And finally, my secret weapon… Trader Joe’s Whole Wheat Bread. I can’t remember its exact name, but it comes in half-rounds and has three ingredients: whole wheat, water, salt. 200 calories, 16g of protein and 16g of fiber per EXTREMELY FILLING slice. You can eat this stuff until your jaw hurts. It’s epic. However, keep in mind that 16g of fiber is a ton. Stay near a bathroom.


What About Exercise?

Remember the basic equation:

Calories stored = Calories eaten - Calories burned

You can lose weight with exercise, but it’s harder than you’d think. Exercising tends to make me hungry, causing me to eat more than I would normally. Plus, it takes a lot of exercise to burn off a significant number of calories. If you vigorously lifted weights for an hour, you’d only burn ~400 calories, less than a single cheeseburger! You’d have to keep that up every single day without increasing your diet to lose a less than a pound per week. I decided it’s easier to simply eat less.

Note that I’m not saying that exercise is not valuable. Exercise has great health, happiness, and life extension benefits. I just don’t think it’s an efficient way for me to lose weight.

What Next?

What next? I think I’m going to try to drive my weight down a bit further and then replace the pounds of fat lost with muscle. Or maybe I’ll get myself to floss every day. We’ll see!

I always thought weight loss was hard because I’d witnessed people throw themselves at it hardcore and then fail just as hard. In contrast, I chose an easy, long-term, data-driven plan and stuck with it. Small changes over a long time make a big difference.

GDC Notes: Comparison of XBLA, PSN, iPhone

On Wednesday of GDC I attended Braving the Stormy Waters of Xbox Live Arcade and PSN: Smaller is NOT Easier. Panel title aside, it was really a comparison of developing for XBox Live Arcade, PlayStation Network, and iPhone. First, a terminology note. I’m tempted to call these games “indie games”, but even companies as large as Capcom are creating games for these platforms. Thus, I’ll call them “small games”. Here are the lessons I took away:

It’s hard to market small games. Use twitter, facebook, or youtube to build a community and spread your game via word of mouth. Go to conferences to spread the word if you must. Viral is the way to go.

It’s okay to ship incomplete as long as people buy into your vision and you continue to release updates. iPhone community is good about rerating updated apps. They gave an example of a game that went from 500th rank to 1 after key updates, but I forgot what it was.

ON THE OTHER HAND: on XBox/PSN, updating is too expensive, because it initiates another round of compliance checks. iPhone looks to be the easiest platform with a 97% app acceptance rate.

XBox 360 allows simultaneous global release of a title. PSN doesn’t. On the other hand, PSN is starving for content, so they’ll be very helpful. But they’re less organized than Microsoft.

Don’t depend on a launch window: you can’t control it. If a high-profile AAA game (Fable 2, say) ships the same week as you, you won’t get any traffic.

Along those lines, digital distribution (DD) is very weak in the traditional retail game season: fall/christmas. Launch your DD games in spring. Maybe someone will figure out how to take advantage of DD at Christmas.

Several people commented that small games are hard. You need to produce a new title every few months, which is very tiring. No time for long, thoughtful showers. You’ll quickly learn which programmers are actually pulling their weight. I got the impression small projects require more talented team members.

No mention of WiiWare, Flash, web, or desktop games.