In the Zero Carb community (us folks who eat only meat, eggs, cheese and butter) there has been much controversy over whether there is a need to limit the amount of protein we eat. I have followed many Zero Carb sites for the last 3 years that I have undertaken this way of eating myself. There seems to be ample evidence that a large number of people are able to reach their desired weight and be vigorous and healthy eating all the protein they want often eating 2-3 lbs of meat per day or in some cases more with no weight gain.
My own experience was that my weight loss on a program of unlimited protein consumption stalled after 4-5 months and after about 4 months of no progress I was able to restart my weight loss by initially limiting my protein. After much study the figure that seemed to be the most recommended by low carb doctors like Stephen Phinney and Eric Westman was to multiply the weight you wanted to weigh in kilograms by 1.5 and use the result as the maximum number of grams of protein you ate in a day. When I did this I was able to lose another 20 lbs before plateauing short of my goal again. The final piece to the puzzle for me was adding intermittent fasting which I won’t get into here but was the key that let me get to my ideal goal weight.
Many people have emailed me with the problem of stalled weight loss on Zero Carb and Low Carb diets and after deciding to limit protein have subsequently gone on to lose significantly more weight after
It has become clear to me that about 60-65% of humans around the globe cannot tolerate high levels of either alcohol or refined sugar without developing insulin resistance. The real culprit is Fructose the sugar that comprises 50% of refined sugar and high fructose corn syrup which is now used to sweeten most products in the industrialized world.
Gary Taubes has detailed the scientific evidence in his masterpiece “The Case Against Sugar” better than I ever could but to summarize fructose can only be metabolized in the liver where in susceptible individual most of it gets turned into fat and stored in the liver and pancreas. Fat is not supposed to be stored in either location and is treated by the body as a “foreign body” and gets attacked by our own immune system. In fact because of this up to 50% of the weight of the fat deposited where it shouldn’t be in our internal organs is often pus (white blood cells causing inflammation). This damages our pancreatic alpha cells that make glucagon. Glucagon is the hormone that makes our blood sugar levels go by encouraging the liver to release stored glucose and to make glucose out of protein. Normally if we eat carbohydrate insulin should be released that will tell the alpha cells there is already enough glucose, stop making glucagon. But in insulin resistant people the alpha cells are inflamed and damaged and instead of stopping glucagon production they either don’t stop and even increase production in the presence of insulin. The high sugar levels from the increased sugar production by the liver stimulate the pancreatic beta cells to produce more insulin leading to high insulin levels which eventually leads muscle cells to also become insulin resistant and since insulin is the hormone that drive fat storage the fat cells begin to fill up with fat. Since fat cannot get out of fat cells when insulin levels are high if the blood sugar drops the body will make you very hungry even though there is tons of food stored in your fat cells. Once all the safe peripheral fat stores are full the body is forced to start storing fat in unsafe and dangerous locations around the internal organs leading to inflammation and all the bad consequences of diabetes. Most diabetes researchers focus on beta cells and insulin production, but some are studying the alpha cells and glucagon production as well. A recent study found that hyperglucagonemia (too much glucagon in the blood) actually precedes the decline in insulin secretion seen in diabetes.”. Here’s a link to some of the studies I found on this.
If you want to find out if you are insulin resistant or not click here to find out. However, 30-40% of people seem to be protected somehow and are able to eat a high carbohydrate diet without this progression. First this tells us that there is some genetic component to susceptibility to developing Insulin resistance – “We don’t all respond the same to carbs”. These lucky people maintain their “Metabolic Flexibility”. Here’s a post I did about that: Metabolic Flexibility – The Ability To Eat Carbs and Protein Without Gaining Weight – Once Lost Can We Ever Get It Back?
Insulin resistance is caused by the same process that leads to fatty liver and fatty pancreas. Once a person is metabolically damaged like this even the 50-75% of insulin release caused by a gram of protein compared to a gram of carbohydrate keeps the insulin level too high for fat to escape the fat cells and be burned. Here are pictures of a normal pancreas and a fatty pancreas and the fat in fatty pancreas is up to 50% inflamed pus cells.
Again, I can’t find any controlled studies on weight loss on low carb diets comparing people who did and did not control the amount protein they are consuming and I doubt they exist so I am left with only anecdotal evidence. But my personal theory is that first some people are born with more insulin resistance than others. My best evidence for this is the 30-40% of people who don’t seem to become insulin resistant even on a high carb/sugar diet. And second I feel that in some people permanent damage can be done in the liver and pancreas that somehow renders them less tolerant of the insulin generated by protein consumption. I feel the group with either a high tendency to insulin resistance or residual damage to the endocrine system (liver, pancreas, spleen, kidney etc.), a group into which I think that I fall can have problems with the lower levels of insulin release that proteins cause.
There are arguments that a high protein intake over values as low as 0.6 grams of protein per kilogram per day can hasten aging, increasing the risk of cancer and lowering immune resistance through activation of the mTOR system. Dr. Ron Rosedale is one of the main proponents of this theory. You can hear his elegant presentation of this theory here. There is a lot of experimental data on animals to support it but no controlled studies on humans so it remains an unproven theory from my perspective. Still I find the evidence strong enough to err on the lower side of protein intake.
My personal position is that if you’re eating 2 lbs (32 oz) of meat a day you are getting about 224 grams of protein since meat averages about 7 grams of protein per ounce. If you weigh 150 lbs (68 kg) thats 3.2 grams of protein per kg per day. If you weigh 250 lbs (113 kg), 2 lbs of meat is still 2.0 grams of protein per kg per day. So if you’re eating more than 1.5 grams of protein per kg per day and you are not losing the weight you think you need to lose to get to a desirable weight and have given it 3-6 months of an honest trial, you might consider a 1-2 month trial of limiting protein to 1.5 grams per kg of desired weight per day. Many prominent low carb doctors recommend protein restriction in this range for patients who are not losing enough weight on carb restriction only. It’s a year now since I wrote this post initially and which I updated today (4/5/18). I have now remained at my ideal weight for 21 months on a zero carb diet employing protein restriction and intermittent fasting, my health and vigor have been exceptional with no illness and even more energy and stamina than before I started protein restriction 2 years ago. I have heard from at least 40 people who have reversed their stall on Zero Carb diets by implementing protein restriction and intermittent fasting. Again if you are having great success with unlimited protein in my opinion you were either not insulin resistant or very mildly insulin resistant and were able to reverse it by eliminating carb. Since it’s working well for those folks I see no reason to change their way 0f eating. Here’s a link to how I limit protein personally.