How Protein Can Help You Lose Weight

eggIs fat loss at the top of your list of health & fitness goals? If so, then you’re not alone. In the U.S. and many other industrialized nations, more than 50% of the population is today classified as either overweight (BMI 25-30) or obese (BMI >30), which means that if you’re normal weight, you’re actually in the minority. This situation hasn’t occured because people like to carry around a lot of extra body fat on their thighs, buttocks, and abdomen, but because many find it almost impossible to make healthy choices and achieve their ideal body weight in the evolutionarily abnormal environment we’ve created for ourselves.

Over the last couple of centuries, and particularly the most recent decades, vending machines filled with cheap soda, chocolate bars, and candy have made their way into schools and work places, junk food has become available on every street corner, and driving has replaced walking as the primary means of transportation. Top that of with the fact that the levels of hormone-disrupting, pro-inflammatory toxins and harmful substances in the food we eat, the drugs we take, and the air we breathe have increased dramatically lately, and you can start to understand why the obesity epidemic has spread like fire in dry grass over the last couple of decades.

There are certainly some people out there who don’t really seem to care about what they eat or whether they’re carrying 10, 20, or 40 pounds of extra fat mass around with them, but these individuals are the exception rather than the norm. If you talk to a person who is overweight or obese, he’ll likely tell you that he wants to lose weight and that he’s tried numerous diets and supplements in his quest for leanness – but without sustained success.

One of the main reasons so many people aren’t able to achieve sustained weight loss is that they don’t know much about nutrition and body fat regulation, but rather just jump from diet to diet, often picking the nutritional strategy that’s trending at the moment or basing their food choices on what the latest edition of their favorite health magazine has to say about what we should eat. Many try to count calories, but when the cravings and fatigue get intolerable – which they usually do if you deliberately restrict your energy intake over long periods of time – they give up, often falling back into old habits.

Designing a slimming diet

To be able to achieve sustained weight loss, we have to acknowledge that the human body is a complex system that has its own mechanisms for regulating body fat storage, not just a passive vehicle that comes along for the ride. If we try to lose weight by consciously restricting the number of calories we eat – without making any changes to the composition of our diet – we can quickly end up feeling that we’re fighting against our own body. Calorie counting, at least by itself, rarely works over the long-term; it just makes us go around hungry and fatigued, until we finally succumb to the desire to eat to satiety again.

To achieve sustained weight loss, we shouldn’t just consider how much we eat, but perhaps more importantly, what we eat. The food you eat affects gene expression, gut microbiota composition, and the inflammatory and hormonal milieu in your body, among other things. By eating the right types of foods, you’ll improve leptin and insulin sensitivity, turn down the inflammatory tone in the GI tract and the body in general, and “reset” your taste buds, all of which are critical to achieving a healthy body weight.

Several factors associated with contemporary Western diets and lifestyles come together to promote overeating and body fat accumulation, and as I’ve repeatedly highlighted here on the blog, I believe focusing on just one macronutrient (“Carbs make you fat!”) or a single lifestyle factor (“Adequate sleep is the key to weight loss!”) is way too simplistic. Rather, to achieve good health and a lean physique, we have to leave our many, if not most, elements of the typical Western diet and lifestyle behind us and return to the template provided by our primal ancestors.

That being said, “just” changing your intake of a single nutrient or dietary component can sometimes be enough to see major health improvements. One such nutrient that plays a particularly important role in body fat regulation is protein.

Our strong appetite for protein is written into our genome

Hunter-gatherers (both contemporary and ancient) typically eat a lot more protein than most people in contemporary, industrialized societies (1, 2, 3). Today, a diet in which 20-30% of total calories is derived from protein is usually classified as a high-protein diet, but from an evolutionary perspective, this intake level is actually not particularly high. Estimates based on interpretations of ethnographic data suggest that hunter-gatherers generally derived between 19 and 35 percent of their calories from protein, which is quite a bit more than the average protein intake of approximately 15 percent in the U.S (1).

If we place ourselves on the African savanna 2 million years ago, mark that as our baseline, and look at the types of diets that have been consumed by members of our genus, Homo, since that time, it becomes clear that it’s more accurate to describe the contemporary Western diet as a low-protein diet, while so-called high-protein diets (>20% of total calories from protein) actually should be classified as having a “normal” protein content.

The levels of protein consumed by hunter-gatherers (about 20-35% of total calories) are the types of intake levels that conditioned the human genome over millions of years, so it makes complete sense that a growing pile of research supports the use of “high-protein diets” in everything from the prevention of cardiovascular disease to weight-loss interventions to the treatment of type 2 diabetes (4, 5).

Protein can help promote weight loss through several different mechanisms

Studies consistently show that so-called high-protein diets offer superior weight loss benefits compared to diets containing low-moderate levels of protein (10-15% of total calories from protein) (5, 6, 7, 8, 9), . This makes complete sense, as we know that protein increases satiety and thermogenesis to a greater extent than the other two macronutrients.

Basically, protein helps you feel full and satiated, thereby making you less likely to “overeat” or get cravings for more food between meals. As for the thermic value, it takes quite a bit of effort for your body to break down and make use of the protein you got from the lean, juicy steak you had for dinner, meaning that the actual amount of calories you derive from the steak is lower than what you’d expect from simply looking at the nutritional information on the label.

Also, high-protein diets may improve leptin sensitivity in the central nervous system (10). This is critical, as one of the main reasons so many people have trouble losing weight is that their brain have become desensitized to the signals from the hormone leptin.

Leptin is secreted by fat cells in proportion to their size and is received by receptors in the hypothalamus. If we carry a lot of fat mass, the brain is supposed to respond to the high levels of circulating leptin by lowering our appetite and ramping up the use of stored energy. However, we don’t have to look far to see that this mechanism doesn’t always work flawlessly, as no one would be overweight if it did.

When the brain becomes resistant to the signal from leptin, it “thinks” the body carries more fat than it actually does and starts defending an elevated “body fat set point” (11). This situation makes it very difficult to lose weight unless leptin sensitivity is improved. As mentioned, eating more protein could help in that regard.

Top all of this of with the fact that several studies both in humans and animals have shown that our appetite for protein is so strong that we “keep eating” in an attempt to reach a targeted protein intake (5, 6), and you can quickly understand why it’s important to make sure you’re eating enough proten if your goal is to lose weight.

This so-called Protein Leverage Hypothesis, which say that we “prioritze” protein intake over total calorie-, fat- and carbohydrate-intake, is  supported by studies which show that individuals given a diet with a low protein content (e.g., 10% of total daily calories) consume more total calories than individuals who are given a diet with a high protein content (e.g., 20% of total calories) (5, 6, 7, 8, 9).

Boosting your protein intake

So, how can we transfer all of this into some real-life, practical applications? I think one of the biggest mistakes people make in their quest for weight loss is that they try to make it through the day by only eating salads, fruits, and other plant foods with a very low energy density. While I definitely think it’s important to focus on the energy density of the food you eat, it shouldn’t overshadow everything else.

If all you eat is a vegetable smoothie for breakfast and a salad with no added protein for lunch, you’re bound to crash later in the day, perhaps devouring everything in sight when you get home from work. However, if you consume some scrambled eggs for breakfast in addition to your smoothie (or better yet, start chewing your vegetables instead of drinking them) and add some chicken to your lunch salad, you’ll feel more satisfied throughout the day and improve your odds of losing the unwanted body fat that has accumulated over the years.

Perhaps needless to say, it’s not just the amount of protein we eat that matters, but also where we get it from. Steer clear of CAFO-produced meats, farmed salmon, eggs from chickens that live in crowded unsanitary conditions, and other similar animal products. Instead, seek out high-quality, organic foods and grass-fed meats.

Finally, I want to make it clear that there’s no reason to go overboard, such as by eating huge steaks every day or drinking raw eggs before bed. Rather, aim for a moderate intake of high-quality protein at every meal.

Personally, I typically derive about 20-27% of my total calories from protein, the exact level depending on how much strength training I do. I find that keeping my protein intake at this relatively high level helps me maintain a lean frame and avoid cravings for unhealthy food.

Now I want to hear from you: How much protein do you consume? Are you going to increase your intake after reading this post?

Picture: Creative Commons picture by This is Akward. Some rights reserved.
Note: A previous version of this article of mine was published by Paleo Magazine, the first, and only print magazine dedicated to the Paleo lifestyle and ancestral health. You can subscribe to Paleo Magazine here!


  1. What about the theory that too much protein can turn into glucose thereby raising insulin? Is there a threshold of protein?

    • Hi Kim!

      I’m not sure exactly which theory you’re referring to. Some amino acids can be used as substrate for gluconeogenesis in the liver, but under normal physiologic conditions, this is not a process that contributes much glucose to the system relative to what you get through your diet (as long as you’re not eating a very low carbohydrate diet). Some proteins, in particular whey protein, are highly insulinogenic, but that’s not because the AA are somehow “converted” to glucose.

      There is a threshold to how much protein you can safely consume. Humans may not tolerate diets that contain more than 35–40% protein by energy. A intake that exceeds this level can lead to “rabbit starvation,” a condition that may be caused by an inability to up-regulate enzymes necessary for urea synthesis.

      Hope that helps! Let me know if you have any further questions.

      • Thank you Erik. Gluconeogenisis is what I was referring to. I do eat very low carb so I can get my blood sugar normalized but some writers say say to eat more protein (for my height-about 98g) and moderate fat and then others say not to eat too much protein (around 50g) and eat really high fat. I also need to lose quite a lot of weight. From articles I’ve read, the key is lowering insulin to normal levels and if you eat too much protein it would contribute to glucose thereby needing higher insulin levels. It’s all very confusing.

    • Gluconeogenesis is a highly metabolic expensive pattern, and your body converts amino acids only for the required amount of glucose, not more to rise insulin as high carb loads do. An italian researcher pioneer in evolutionary diet, developed a diet designed for agonist bodybuilding and it relies on gluconeogenesis pattern to get shredded for the contest. It’s quite an extreme diet to be used only for a limited amount of time but enlights how a high protein intake can make you lean. For a normal person who wants to gain muscle if we want to generalize a bit the average protein intake may be ~2-2.5 g/kg while for the others may be fairly lower.
      Anyway, in the protein case, I think your cravings can be mostly reliable and you may safely follow them. Your body will guide you. For carbs it may be more difficult because of the delicate mechanisms and feedbacks they trigger in our body and brain.

  2. Hi Eirik. I typically eat some animal protein at every meal. I don’t measure the amount of protein I eat. When I’ve had enough, I lose interest in eating any more. I tried going vegetarian a number of years ago, and it was a disaster. I was always hungry and tired and didn’t feel quite up to par, even though I was consuming a lot of food. When I actually dreamed of eating steak, that was the last straw. I ran out and bought one. I broiled it medium- rare and ate it with a salad and some root veggies. I think that was the best meal I’ve ever had. And probably the most enlightening one. Some people thrive on a vegetarian or vegan diet, but I’m definitely not one of them.

    • I don’t measure how much protein I eat either, I simply go by my appetite. There’s no reason to complicate things by measuring everything you eat or counting exactly how many grams of protein you take in every day.

  3. Hi Eirik, hope you enjoyed a Happy Holiday season! I always look forward to your blogs.

    Currently, I’m using a macro split of 35-40% protein, 35-40% carbs & 20-30% fat on the days I workout usually Monday – Friday and use a 30-40% protein, 30-35% carbs & 30-35% fat ratio on the weekends when I don’t workout. I admit I’ve been playing around with my macro splits to try to find out what is optimal for me.

    Although I have a desk job I try to stay pretty active usually completing 15k+ steps/day, taking classes in Krav Maga 3 times/week & usually complete 4-5 fully body workouts using compound lifts &/doing some kind of cardio (skipping, running, ladder/bosu/cone drills, a Zumba or step class etc.). I include some yoga, foam rolling, etc. on top of this.

    • Good to hear from you again, Alison.

      35-40% protein!!?? Are you sure you’re taking in that much? If that’s correct, then I would really like to hear your experiences (i.e., in terms of body composition, food cravings), as I’ve never consumed that much myself or had clients that take in so much protein.

  4. Hi Eirik,
    I don’t weigh my food & eat more or less until I’m comfortably full so macros are a guess estimate. For my own curiosity I’ve started tracking my food intake & exercise online but again % accuracy is a good question. I’ve learned to use my hands to guesstimate portion sizes (precision nutrition).

    As for the 35-40% protein intake on weekdays I started working out with a trainer, NSCA, Twist Conditioning & sports nutrition certified, he recommended increasing my protein based on his knowledge of how I workout & train. It’s early days on the upped protein, I just started increasing protein intake in the past week or two. I can tell you night cravings for fat and/or carbs is almost nonexistent at this time, I’ve dropped about 1.5 lbs (related to consuming too many nuts/hot air popcorn with butter or coconut oil, almond butter, etc.?). In terms of fat % I only have regular access to a Tanita scale. Last time I was on it body fat was at 22.5% but I have doubts on its accuracy, might be interesting to hop on it again just for curiosity. One other interesting thing I’ve noticed this week is that the quantity and quality of sleep I’ve gotten is substantially better, on average I’ve been sleeping 7-7.5 hours/night without waking up until morning, compared to 6-6.5 hours sleep/night & waking up once most nights prior to increased protein uptake.

    If you’re interested I can keep you updated in another couple of weeks on progress, &/or if you have any further recommendations for me I’d love to hear from you.

    • In terms of body composition, I’ve never really paid close attention to that. I judge myself based on performance & body comp for me is a side benefit of what I do. To me, Increased weight/reps/less rest between sets, new PRs & how I feel about my workouts/recovery & General performance compared to previous sessions is top priority.

    • Sounds good. Thanks for sharing!

      As for my recommendations, my immediate thought is that 35-40% protein is too much. While I’m all for a protein intake that is somewhat higher than what the average dietitian recommends, there’s no reason to go extremely high 🙂

  5. I’m thinking of taking liver tablets to up my protein. I’m one of the people who do a green smoothie for breakfast and a salad for lunch then all downhill from there. Is it a good idea to supplement with liver tablets?

    • Hi Patti!

      Sounds like you could greatly benefit from adding some more protein to your diet.

      That being said, I don’t recommend supplementing with liver tablets. Stick to real food (i.e., meat, fish, eggs).

      Let me know if you have any further questions.


  1. […] diets (>20%) are effective in the prevention and treatment of a range of health problems, in particular metabolic disorders and obesity (3) . This doesn’t mean that you have to eat a lot of protein, however, there is little doubt […]

  2. […] Online, you’ll often see claims that fat is the most satiating macronutrient. I’ll argue that this notion is not supported by the scientific evidence. I’m by no means opposed to the consumption of all high-fat foods (I actually eat a diet that is fairly high in fat myself), but I don’t think it’s a good idea for someone who wants to stay satiated and lose weight to eat a lot of butter, bacon, cream, and similar high-fat foods. If increased satiety is what you’re looking for, protein may be your best bet, because this macronutrient increases satiety and thermogenesis to a greater extent than the other macronutrients, can improve leptin sensitivity in the central nervous system, and boost weight loss. […]

  3. […] As I’ve pointed out in many of my previous articles, I think the vast majority of people, in particular those who are trying to lose weight and/or grain muscle, would benefit from including more high-quality protein in their […]

  4. […] effect on satiety and thermogenesis, and there is convincing evidence that protein intake has a significant impact on total calorie intake. If you eat a diet that contains inadequate amounts of protein, you would likely consume more total […]

  5. […] are based on nitrogen balance studies, recommend. This goes for both men and women. Protein can help you lose weight, build lean muscle, curb undesirable food cravings, and combat chronic […]

  6. […] Protein has a higher thermic value than the other macronutrients, promotes satiation and fullness, may enhance sleep quality, and can improve leptin sensitivity in the central nervous system, among other things. Furthermore, research looking into the protein-leverage hypothesis has shown that humans (as well as many other animal species) who are instructed to adhere to a so-called high-protein diet tend to consume less total calories than individuals who are instructed to eat a low-protein diet (4). It’s therefore not surprising that numerous studies have shown that high-protein diets are effective in the prevention and treatment of obesity and the metabolic syndro…. […]

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