For the last twenty-three years, I have been eating only one meal a day. I adopted this habit long before I heard the term “intermittent fasting,” which is now the common term for a eating schedule that includes long gaps between meals. In the manner of all research involving nutrition, there have been numerous studies showing that intermittent fasting is good for you, as well as some studies suggesting that the benefits of intermittent fasting have been exaggerated. But I have my own reasons for preferring to eat one meal a day, which is probably a habit I will maintain for the rest of my life.

I have four basic arguments in favor of this schedule: human history, dieting, healthy eating, efficiency, and pure pleasure.

First, as the saying goes, there is no fossil behavior, and scattered observations of isolated tribes apparently still living like our ancestors are not definitive proof of the way that they lived. But I think that one thing is clear: ancient humans did not wake up and have a hearty breakfast, work for a few hours before eating a lunch, and doing some more work before eating a dinner. That three-meal-a-day routine, which so many people rigidly follow, is a late arrival in human history, probably first developed less than ten thousand years ago.

This is how I envision the lives of prehistoric tribes: they woke up in the morning hungry, and while they took some time for other tasks like establishing shelters, devising tools, and making clothing, their primary activity during the day was an urgent search for food. Though some have questioned traditional assumptions about fixed gender roles, it is commonly accepted that the men would pick up their weapons and go out to spend the day hunting, while the women would go to work gathering edible plants, nuts, vegetables, and fruits. At the end of the day, they would reunite, share the results of their efforts, and put together a meal using whatever the men and women had found. If the hunters were successful, they mostly ate meat; if they were not, they mostly ate nuts and berries. Then, with full bellies, they would go to sleep to get some rest in preparation for the next day’s search for food.

So, when I go without food for a long time before eating one meal, I feel that I am following the natural pattern of human evolution, altered only when the rise of civilization allowed them to eat more frequently. It did take some adjusting at first, but now my schedule feels totally normal, and when people notice that I haven’t eaten for a while and solicitously ask, “Aren’t you starving?,” I reply that I am fine; I am behaving in a time-honored fashion, and it is they who are departing from ancient traditions to constantly engage in eating.

Second, the primary reason I adopted this habit in the first place was a desire to lose weight. In 2003, I attended a conference in Hong Kong, and looking at the pictures from the event, it was painfully obvious that I was getting a little chubby; so, I was determined to get back to a respectable weight. Now, when my wife wants to lose weight, she sets a daily limit for how many calories she can consume, carefully notes the calories of every item she eats, and maintains a daily tally until she has consumed her total amount of permitted calories for the day and eats no more. This sounded too complicated for me. It seemed simpler to limit the amount of time that I ate; if I only ate for one hour a day, I reasoned, I couldn’t possibly overeat, and I would inevitably lose some weight. Actually, my initial schedule was more extreme: I would fast all day every Monday, and eat one meal on the other six days. My plan worked, and when I was down to a desirable weight I abandoned the weekly fasting and now eat seven meals a week, though I will still occasionally fast for a day when my schedule makes it challenging to squeeze in a meal.

I should note that, in my experience, the weight loss brought about by eating one meal a day is not permanent, because as my body grew used to the regimen, I started to gain weight again, and while I now weigh more than I like, I am not obese, and I am no longer concerned about being slightly overweight.

Third, eating one meal a day virtually forces you to have a healthier diet. Let’s face it: when you haven’t eaten for twenty-three hours, you don’t want popcorn or candy bars; you want nourishing food. So I usually begin with a salad, have a main mean of protein, starch, and vegetables, and if there is room, a little dessert. And I don’t miss junk food at all; instead, I have grown to especially enjoy my daily salad, as I constantly experiment with new items to add, and I sometimes have to force myself to conclude by eating some ice cream in order to get some dairy products into my system. I also feel that my meals are healthier because I long ago became a vegetarian, but the benefits of that diet is a topic I have already addressed.

Fourth, eating only one meal a day gives you more time to work on the things you want to work on and indulge in the other activities that you enjoy. Bluntly, it takes a lot of time to prepare and eat three meals a day, and if you’re like me, eating also can make one drowsy for a while, further diminishing one’s productivity. I might have gotten this idea from a book I read long ago, Upton Sinclair’s The Book of Life (1922), in which he recommends one meal a day for precisely this reason. If you have a lot of things to do, he advised, don’t eat all day; that maintains your energy. Indeed, the notion that you require periodic intakes of food to keep doing your best work is a complete myth; for as Sinclair noted, when you don’t eat, your body draws upon its stored reserves, and they are the best fuel around.

So, when I wake up in the morning, I briefly check my email and a few news websites, then I can immediately go to work, without taking the time for a meal; and when I had a full-time job, I could use my lunch hour to go to the library and do research. One reason I have continued to be very productive is that I simply have more free time than other people because I am not regularly wasting time by unnecessarily stuffing my face.

Finally, when you only have one meal a day, you really look forward to it, and you really appreciate and relish eating when you finally have an opportunity. And let’s face it: pausing every so often to consume an obligatory meal sometimes feels like a chore. I recall one cold morning on the campus of the University of California, Riverside, when I saw a bundled-up student standing on a sidewalk and wolfing down a sandwich before she went off to class. And I thought to myself: is this student really enjoying her meal, standing outside in the cold and rushing to finish it? Wouldn’t she have been happier if she had simply skipped that meal, gone about her business, and waited to eat until she could do so calmly and comfortably. That’s the main reason I feel sorry for people who eat constantly, because eating so often diminishes the simple pleasure of eating.

As I write this, it is 7 AM on a Friday morning and after I finish this up, and not feeling hungry at all, I will immediately move on to two more writing tasks that I want to complete today before I finally settle down to my much-anticipated and leisurely one meal of the day, satisfied that I have made some significant accomplishments while maintaining a healthy and satisfying diet. It is a schedule that I would recommend to everyone.