1.5 Meals a Day (OPFMAD): OMAD for High-Performers


Intermittent fasting, one meal a day (OMAD), eating every other day, the “lean gains” protocol, or the bodybuilding style of snacking every two hours.

Which is best?

Meal timing has become a hot topic as more research shows that when you eat matters as much as what.

Indeed, my own experiences with a technology called continuous glucose monitoring, showed that eating healthy food late at night spikes my blood sugar higher than binging junk food at normal times.

Having investigated the current science and ancestral medicine, I’ve come to favor a new approach I call 1.5 Meals a Day (OPFMAD — if you will). This post explores why I’ve found that most people do best eating a massive lunch and small dinner.

Problems With 3+ Meals Per Day

Today, eating three or more meals per day seems normal. Only recently did humans gain unfettered access to food. Supermarkets brimming with foods, and convenient ready-made snacks encourage around-the-clock consumption.

There’s a dark side of eating many small meals throughout the day. Here are some of the drawbacks:

Expensive. Snacking foods cost disproportionately for their weight and able to satisfy. Snickers bars, for example, cost more per once than grass-fed beef.

Time inefficient. If you cook for yourself, each additional meal takes extra prep time. But even if ordering out, you waste time choosing a restaurant, what to order, and preparing for the meal. Plus, digestion costs energy in the short-term. Energy that you could put elsewhere.

Unhealthy. Snackers often consume more total calories than their counterparts. Little bites here and there keeps the hormone insulin artificially increased throughout the day. Over time, you’ll develop insulin resistance and metabolic dysfunction. Then, satisfying appetite requires more calories. Often leading to obesity and other complications.

Unstudied. Never in our evolution did humans have 24/7 unfettered access to calorie-dense nutrition around the clock. Our biological coding expects regular periods of fasting. Our ancestors regularly fasted — not by choice. Every day scientists uncover more reasons to fast, and consequences of the modern food oasis.

Dangerous. Feeding activates the anabolic protein mTOR and suppresses the catabolic protein AMPK. Only when AMPK is elevated, do the cellular cleanup processes of mitophaghy and autophagy occur. Some research suggests that chronic activation of the anabolic protein mTOR may lead to cancer and serious diseases.

Weight gain. Manufacturers make popular snacking foods shelf stable, palatable, and long-lasting. I am not diabetic. But my experiment with a continuous glucose monitor (CGM) illuminated that many so-called “healthy” keto/low-carb snacks actually spiked my blood sugar higher than certain fruits. Hidden ingredients combined with decreased insulin sensitivity and increased appetite can lead to rapid weight gain.

When looking to pack on weight and grow, I use periods of three or more meals per days. Then I make sure to go to the other extreme and activate the longevity pathways. Sometimes I’ll use another short-term tactic called OMAD.

Problems With 1 Meal Per Day (OMAD)

On the other end of the spectrum, folks following OMAD eat just one meal a day (see where the name comes from?). In many ways, it’s become the antithesis of the traditional bodybuilding diet.

I use it strategically, but not long term. I wrote about my experience with OMAD here.

From months of personal trial and talking to other OMAD’ers, these are the major drawbacks:

Insufficient growth. Where the bodybuilding approach over-activates the anabolic protein mTOR (at the cost of disease related to over-growth), OMAD over-activates AMPK. Constantly breaking down bodily systems without significant anabolic rebuilding can lead to degenerative diseases and inability to maintain (or build) lean body mass. Since lean body mass is one of the greatest predictors of longevity, I’m wary of minimalist feeding programs.

Hormone dysregulation. Several hormones commonly go out of balance. Chief and most concerning, is cortisol. Eating blunts this stress hormone. With fewer meals, it stays artificially high and can lead to HPA-axis dysfunction (sometimes called “adrenal fatigue”). The less often you eat, the more your body produces the hunger hormone ghrelin. Thus people often complain about constant hunger. Women in particular experience problems with Gonadotropin-releasing hormone (GnRH) leading to lower estrogen and progesterone levels.

Anxiety around meals. Prior to OMAD, I didn’t worry much about when I’d eat. When life happened and something came up, I knew that I’d get to my meal soon enough. Eating this style made me wonder if something—however small—would interfere with my sole meal of the day. It got to the point where I started planning my day around my meal. Slightly defeating the whole liberated-from-constantly-eating perk.

Requires strict scheduling. When you eat makes a big difference. You must choose either breakfast, lunch, or dinner. Each has benefits and drawbacks. Stick to the time. Your body and gut microbes digest best on a consistent schedule. Deviating often causes blood sugar spikes and greater inflammation, leading to worse nutrient absorption and unhealthier meals.

Anti-Social. Humans come together around food and drink. No matter how you do it, OMAD secludes you from one or more major groups. Either you skip lunch and eat dinner with family or friends. Or skip dinner to eat lunch with coworkers. In both cases, its unsocial nature alone made me stop.

Digestion. If in perfect condition, your body can use the long time between meals to heal the gut. That aside, how many calories do you eat per day? 2,000 calories in a single meal overloads the body’s digestive processes. When trying to maintain weight, I ate about 4,000 calories per day. I found the sheer bulk of the food difficult to consume every day. In fact, it felt like a chore. And I didn’t feel that great when putting down mountains of food. My first real experience with bloat, heart burn, and acid reflux. Some people combat this with bandaids of digestive enzymes, pepsin, and artificial stomach acid boosters.

Nutrient-deficiency. Then there’s the issue of anti-nutrients. Lectins, trypsin-inhibitors, phytates, and the like present in all kinds of foods inhibit absorption of certain nutrients. Notably vital vitamins and minerals. Supplements generally aren’t as bioavailable as nutrients in whole-foods. I see this as a major pitfall of OMAD.

All that said, I still find OMAD a useful tool and use it during my yearly metabolic reset. But for the most part, I use a different approach.

1.5 Meals Per Day is Best

Wondering what 1/2 of a meal looks like?

The way I do it, its just a lighter meal. Generally higher in protein and fat.

Overall, it’s the ideal balance between OMAD and the bodybuilding style. This is why I eat one huge meal, and one small meal on most days.

Ancestral. Previous humans might not have had supermarkets down the road. They’d go hunting and probably wouldn’t eat six evenly spaced meals throughout the day. Between large meals, our ancestors could easily forage for berries and plant-based foods.

Eating two meals. You don’t become the social outcast never eating with friends or coworkers. Two meals also relieves the anxiety around potential obstacles preventing you from cramming all your day’s calories into a one-hour window.

Longevity and performance balancing. The protein AMPK corresponds to longevity and mTOR to performance. Activating one proportionately inhibits the other. The second meal gives you the ability to control the balance however you desire. You can add more protein and carbs to stimulate mTOR, or fats for greater AMPK.

Efficient. Like OMAD, having a quick pre-made smoothie, or easily meal-preppable half meal frees up significant time to spend on other things that matter. It’s also budget efficient.

Carb backloading. Depending on how you do it, you can still get the performance benefits of evening carbohydrates for sleep, thyroid, etc. This keeps you in fat-burning mode and in ketosis throughout the day. Then in the evening, when glycogen stores have depleted, you can add back carbohydrates.

Sleep improves. For most of the meal times I tested on OMAD, my sleep suffered. If I ate breakfast, I’d constantly go to sleep hungry. Oura showed significant worse sleep onset time. Choosing lunch caused the same issue, albeit less. When I ate a huge dinner, I’d go to bed uncomfortably full, and my sleep quality would decrease. On the otherhand, no matter if I chose the large meal or small for dinner, I saw my sleep scores rise consistently. The second meal (or half meal) made all the difference.

Circadian rhythm. The body has an intricate system of internal clocks. Clocks that run on a ~24.1 hour schedule. While it seems close enough to traditional time clocks, over time this small difference adds up. Every day we require certain cues to reset our internal clocks. After light, meal timing is the next most significant. Eating twice per day sends our biology time cues.

After many years of testing, I favor eating one huge meal and one small meal on the days that I am resting and recovering. For me, I heed the ancient Ayurvedic advice and make brunch the biggest meal of the day. Just before sunset, I have my small half-meal dinner and reap the benefits.

One Point Five Meals Per Day For Most

Forgive me for not having a sexier acronym. OPFMAD doesn’t exactly roll off the tongue.

Of course, one-size-fits-all approaches rarely work. Meal frequency and timing is no exception.

How often I suggest eating depends on your current goal: growth or repair?

Bodily processes can only prioritize one at a time.

For the young, pregnant, or athletic, prioritizing growth by eating more supports your goals. Maximizing growth, however, can lead to conditions related to excessive growth.

Most people, however, already send their body growth signals around the clock. They could use more time in repair mode — coming at the cost of greater difficultly adding lean body mass.

When growth is a priority, I’d follow something like the Weston A Price diet which emphasizes clean, nutrient-dense and high-calorie foods.

For the rest, I’ve seen great results from people eating one large meal and one small.

I like to fluctuate. On my intense training days, I’ll eat two or sometimes even three full meals. Then on lighter recovery days, I’ll switch to OPFMAD, or in rare cases, OMAD.

What have you found works best for you? Let me know in the comments below.

Nick Urban

Nick Urban is the Founder of Outliyr, an expert biohacker of 10+ years, Data Scientist, Certified CHEK Practitioner, host of the Mind Body Peak Performance Podcast, and a High-Performance Coach.

Affiliate Disclosure

This post may contain affiliate links, which means I receive a small commission if you make a purchase to support my work at no cost to you. Thanks for your support!

Leave a Comment