Throughout our entire lives we have been programmed to believe hunger is a bad thing. Three meals a day or bust! And if you are in the business of building muscle and/or burning fat, you are more likely to practice the 4-6 meal a day trend. But why? Who determined that three meals a day was the foundation of a healthy eating plan? Lately, research is suggesting, not only may three meals a day be unnecessary, but you may actually be sacrificing certain benefits that are associated with eating less frequently. One major benefit of eating less often is the presence of a muscle building/fat burning hormone associated with hunger: Ghrelin.
What is Ghrelin?
Ghrelin is a hunger-inducing hormone produced in the stomach. It is present when the stomach is empty, and signals to your brain that you are hungry. Ghrelin levels are high before meals and low after meals. When Ghrelin is present, and we experience a hunger response, most of us head to the refrigerator for a snack or a meal, decreasing Ghrelin, and therefore relieving our hunger. However, by doing so, we miss out on many of the benefits that Ghrelin can offer–such as its potent ability to stimulate Growth Hormone.¹
Ghrelin and Growth Hormone
People regularly spend thousands of dollars on supplements that can supposedly raise growth hormone levels, in hopes of experiencing muscle gains and fat loss. However, what most people don’t realize is that simply eating less frequently–and allowing Ghrelin to be present in the body–can be an effective way to raise one’s growth hormone levels. In order to take advantage of these elevated GH levels, it is important to workout while Ghrelin levels are high. But the benefits are not limited to physical fitness.
Other Benefits of Ghrelin
Aside from increase GH levels–which can lead to muscle gain and fat loss–Ghrelin has numerous other benefits. For example, studies have shown that Ghrelin can have positive effects on learning and memory, and that learning may be best during the day when Ghrelin levels are high². Another potential benefit of Ghrelin is its ability to defend against symptoms related to anxiety/depression brought on by high levels of stress³.
How to Take Advantage of Ghrelin
One easy way to start taking advantage of the muscle building/fat burning effects of Ghrelin is to eat less frequently. There are a variety of diets built on the principal of Intermittent Fasting–two of the most popular being the Warrior Diet, and LeanGains. Warrior Diet is centered around 20 hours of fasting, followed by a 4 hour eating window, generally in the evening time frame. You can see my more detailed description of this diet here. LeanGains practices a 16 hour fast, followed by an 8 hour eating window. There are two important rules to follow in either of these diets.
- Workout during the “fasted” state, preferably before your first meal. This will allow you to a) workout when Ghrelin levels are high, taking advantage of elevated GH levels, and b) allow you to replenish your body immediately after the workout with your first big meal.
- Condensing your eating window does not mean eating less calories. You still want to make sure that you are eating whatever amount of calories correlates with your fitness goals–for example, a small deficit when trying to burn fat, or a small surplus when trying to gain muscle. Eating the same daily amount of calories in a short window of time may be difficult for some people, but the benefits can be worth it.
Conclusion, and Implications for Warrior Diet
It turns out that breakfast–the supposed “most important meal of the day”–actually decreases the important hormone Ghrelin, and therefore can sabotage our pursuit of better health and a better physique. Even further, by suppressing Ghrelin with frequent meals, we may be missing out on an elevated ability to learn, remember the things we learn, and an effective defense against the effects of stress. In order to reap these benefits, the solution may be as simple as postponing our first meal of the day. While our ancestors likely needed elevated Ghrelin levels–and therefore increased GH, mental alertness, etc–in order to hunt and kill their prey, we can still adopt the same “template” of daily eating in the evening. In today’s world, instead of tracking wild animals, we can utilize Ghrelin’s benefits each day at work, as well as in our workouts, and follow it up with a large meal to prepare us for the next day.
¹ Kojima M, Hosoda H, Date Y, Nakazato M, Matsuo H, Kangawa K (1999). “Ghrelin is a growth-hormone-releasing acylated peptide from stomach”. Nature 402 (6762): 656–60.doi:10.1038/45230. PMID 10604470.
² Diano S, Farr SA, Benoit SC, McNay EC, da Silva I, Horvath B, Gaskin FS, Nonaka N, Jaeger LB, Banks WA, Morley JE, Pinto S, Sherwin RS, Xu L, Yamada KA, Sleeman MW, Tschöp MH, Horvath TL (March 2006). “Ghrelin controls hippocampal spine synapse density and memory performance”. Nat. Neurosci. 9 (3): 381–8. doi:10.1038/nn1656. PMID 16491079.Lay summary – Science Blog.
³ Lutter M, Sakata I, Osborne-Lawrence S, et al. (June 2008). “The orexigenic hormone ghrelin defends against depressive symptoms of chronic stress”. Nat. Neurosci. 11 (7): 752–3.doi:10.1038/nn.2139. PMC 2765052. PMID 18552842.