When a low carbohydrate diet is started, weight loss usually occurs rapidly and easily. Although the initial loss is partly water weight, with consistency, body-fat loss continues until ideal body weight is reached. This usually happens without much discomfort.
There are occasionally exceptions to this experience. I previously recommended staying well hydrated, not being afraid to eat fat, and adding a little extra salt to improve the transition to a low carbohydrate diet. Metabolically, your body is designed to switch over to fat burning when carbohydrates are restricted, and this transition occurs over a matter of weeks.
But some people have a difficult time sticking to this plan. Hunger doesn't always diminish. Eventually willpower is exhausted. What is going on?
This happens most often in people that have struggled with weight for a long time. This could be long-standing obesity or yo-yo dieting.
INSULIN CAUSES OBESITY
I previously discussed the importance of insulin in weight loss/gain. Gary Taubes in "Why We Get Fat And What To Do About It," makes a very well supported argument that elevated insulin causes us to gain weight, and makes it difficult to reduce weight, even with calorie restriction. Recall that carbohydrates are the primary driver of insulin. A low carbohydrate diet reduces insulin levels and thus allows weight loss.
Jason Fung in "The Obesity Code" discusses the importance of insulin resistance. This is a common problem and often underlies difficulty with weight loss.
Our bodies maintain homeostasis. That means they adjust to the situation to maintain consistency. Let's see how this works with insulin. When a person eats a meal containing carbohydrates, their blood glucose level will rise. To maintain homeostasis (consistent blood glucose level) the pancreas secretes insulin. This elevated insulin level drives the blood glucose into cells to be burned as energy or stored as fat. It simultaneously stops mobilizing fat from storage since energy is plentiful. This is all good.
Now let's assume the person eats a high carbohydrate diet consistently, just as recommended by the government. The insulin level is elevated throughout the day. Because insulin drives glucose into cells, the blood sugar level drops and appetite increases. So they reach for a snack. Usually this is a high carbohydrate snack or beverage. This again raises insulin. Some have recommended "grazing." This means eating many small meals throughout the day. Obviously this will maintain a steady flow of carbohydrates into the bloodstream, with the resulting elevation in insulin level.
As an aside - It is highly doubtful that our ancestors evolved during times when high-carbohydrate foods were available at all times. In fact it is doubtful that hunter-gatherers had constant access to ANY foods. So the idea that eating all the time (even when driving) makes any sense is ridiculous.
Anyway, because elevated insulin causes weight gain, the person gains weight. Homeostasis applies to cells specifically, just as it does to the body in general. What does this mean? As fat cells get increasingly full of stored fat they become increasingly resistant to additional storage. Because insulin is the hormone telling them to store more fat they become insulin resistant. This happens throughout our body. The body responds by further increasing the insulin secretion until blood sugar drops into the desired range. This cycle continues over and over. Insulin resistance worsens over time. The ever higher insulin level prevents mobilization of body fat for energy and increases appetite, intensifying the problem.
THIS CYCLE MUST BE BROKEN TO ACHIEVE WEIGHT LOSS.
Carbohydrates are the most powerful driver of insulin. Protein also causes insulin release, but significantly less than carbohydrates. Dietary fat causes minimal insulin release. Usually, insulin resistance improves dramatically when carbohydrates are restricted.
If you struggle with a low carbohydrate diet, if you feel hungry all the time in spite of eating dietary fat, if weight loss stalls, you very likely have significant insulin resistance.
WHAT TO DO?
1- Make sure you are really not eating carbohydrates. They are snuck into everything- especially processed foods and in restaurants. Read labels. Even better- make your own food. Stick with non-starchy vegetables and meats and dietary fat.
2- Don't eat tons of protein.
3- Avoid artificial sweeteners. Although they contain minimal to no calories, studies have shown they cause insulin release. That diet soda will actually make you fat. Avoiding sweet tasting foods will gradually reduce their desirability.
4- The most powerful way to break through insulin resistance is with fasting. Our pancreas secretes insulin as we prepare to take a bite of food. Additional insulin is released during chewing and swallowing in anticipation of the subsequent blood sugar elevation. Therefore, completely avoiding food will minimize insulin levels. Back to homeostasis. As our blood insulin level drops, our cells release stored body fat for energy. As we maintain a low insulin level by extending the fast, our cells will become more sensitive to insulin again. This can actually reverse insulin resistance. Although fasting initially sounds crazy, it turns out to be fairly easy.
Soon after beginning to eat a low-carbohydrate, high-fat diet I found myself eating because it was "time to eat" not necessarily because I was hungry. Without doing much research at the time, I decided to skip a meal and see what happened. Amazingly, I found that when I skipped lunch I made it all the way to dinner. I did not instantly lose all my muscle mass, nor did I experience lack of energy. Then I skipped breakfast and lunch. This felt strange to me as it was contrary to the often recited recommendation to eat many small meals throughout the day. I had repeatedly heard that skipping breakfast increases the likelihood of developing obesity and diabetes. Loss of lean muscle mass was also commonly cited. It seemed like I was embarking on exactly the wrong path.
And yet it made no sense to me to eat when I was not hungry. Especially when I felt better during the fasted state. It seemed to me I had stumbled upon yet another myth of modern nutrition- that humans need to be eating constantly. Thinking back to a time before industrial food and agriculture companies, our ancestors were hunter gatherers and probably experienced widely varying caloric intakes over time. Perhaps intermittent fasting was actually the normal situation back then. Individuals that thrived under such conditions would have been more likely to pass on their genes to future generations. In the modern day, with abundant low nutrient density foods omnipresent, those genes that led to survival back then may have become counterproductive. Perhaps if we mimic ancestral conditions by varying food intake as opposed to continually flooding our bodies with food we also will thrive.
There have been many studies on this topic and most show intermittent fasting is likely to be quite good for us. Let's look at some of the major findings:
The concept of the yo-yo diet is well known. Diets, in the traditional sense are temporary, unpleasant restrictions in food quantity that result in some amount of weight loss. Once the diet ends, most people regain all the weight they lost and usually a little bit more. Over time they end up gaining weight. This is not metabolically healthy. Studies investigating intermittent fasting have shown reductions in both body weight and body fat while maintaining or even adding lean body mass.
Additionally, people tend to find intermittent fasting much more sustainable than simple caloric restriction. This is probably because intermittent fasting may induce a temporary state of nutritional ketosis, especially when done as part of a low-carbohydrate, high-fat diet. Ketosis fuels your body with fat metabolites (ketone bodies) and thus suppresses hunger and provides abundant energy during the fast.
Studies consistently show improved insulin sensitivity as a result of intermittent fasting protocols. Remember our discussion of increased baseline insulin secretion that results from exposure to a high-carbohydrate diet? Intermittent fasting reverses this. When not exposed to carbohydrates and proteins for a period of time, the pancreas is able to reduce insulin production and our cells then are exposed to lower insulin levels. The cells in turn will up-regulate their insulin receptors. And just like that, insulin sensitivity improves. It makes sense and studies confirm this.
Heart attack animal models have shown less heart muscle damage after myocardial infarction (heart attack) if the animal was on an intermittent fasting protocol. Additionally, lipid profiles improve with intermittent fasting. Increased HDL(good cholesterol), decreased triglycerides and decreased total cholesterol were seen in multiple studies. Reduction in systolic and diastolic blood pressure that results from intermittent fasting places a decreased load on the heart. Lastly, intermittent fasting resulted in markedly improved survival in a congestive heart failure animal model. It should be noted that lipid profiles do not necessarily improve in patients with familial hypercholesterolemia, and this technique should probably be avoided in this unique situation.
Intermittent fasting has been found to reduce neuron damage in animal stroke models, reduce spinal cord demyelination in multiple sclerosis animal models, prevent age-related impairment of brain function, increase neuronal resistance to injury, and may even protect neurons against the degenerative changes that cause Alzheimer's dementia.
Patients commonly report feeling reduced anxiety and improved ability to focus during a fast. Studies report reduced impulsivity, decreased anger, decreased confusion and improved vigor while on an intermittent fasting protocol.
Immune System Support
Mice adapted to intermittent fasting showed an improved immune response to, and faster clearance of a Salmonella infection compared to those allowed to eat freely.
Since we have been discussing a variety of protective effects associated with intermittent fasting, it comes as no surprise to hear that intermittent fasting is associated with reduced inflammatory markers in blood tests.
Caloric restriction and ketogenic diets have been show to be effective against some cancers in animal models. Dormant cancer cells are dependent on anaerobic glucose metabolism. These cells can result in cancer relapses. Since blood glucose levels can be decreased by up to 40% during fasting, it is felt that fasting may cause these dormant cells to die. Early prostate cancer animal studies show a trend toward improved survival in the intermittent fasting group.
Mice that had adapted to intermittent fasting suffered less damage when exposed to gamma radiation. This protective effect was lost when the mice were allowed to eat freely.
In addition to the potential health benefits, there are some more immediate, practical benefits of intermittent fasting as well:
It is free. I recommend consuming grass-fed, grass-finished meats, wild caught fish, and organic vegetables whenever possible. These foods are more expensive than the standard versions. Skipping meals helps to offset this expense.
It is fast. You will not have to spend any time preparing breakfast or lunch on fasting days.
Improved productivity. The lunch hour is now free-time during which other things can be done.
How to do it?
1- Train your body to burn body fat for energy. This will greatly facilitate transitioning into intermittent fasting. In my case it happened automatically. Read my earlier blog postings for details. Start with carbohydrate restriction, make sure you are eating the proper amount of protein, and don't be afraid to eat fat. You must eat fat to burn fat.
2- Your body will adapt to preferentially burning fat over a period of weeks. During the first two weeks you may feel a bit strange, you will likely lose 10 or more pounds. Stay well hydrated and eat healthy fats when hungry.
3- Within 6 weeks of beginning a low carbohydrate diet many people easily and automatically transition into intermittent fasting. If you would like to try this - simply skip breakfast and lunch and eat a proper dinner. Stay well hydrated throughout the day. Black coffee and tea can be consumed during the fast. To sleep properly, stop consuming caffeine by 2PM. Water should be consumed throughout the day.
4- It appears the beneficial effects of fasting require at least 12 hours without eating, and benefits increase with longer fasting periods. Although fasting can safely be extended beyond 24 hours, most people do not need to. Because eating is also a social event, I prefer fasting from after dinner until dinner the next day. This way I can sit down and enjoy eating with my family, and it provides me an easily sustainable 18-20 hour fasting period. Sleeping through a large portion of this fasting period makes this even easier.
5- Bulletproof coffee. This is a "biohack" developed by Dave Asprey. Adding some butter and coconut oil or MCT oil to black coffee and then blending, it creates tiny droplets of fat suspended in the coffee. Try a teaspoon of each to start and adjust as needed. At first this might seem like it would be unpalatable, but I encourage you to try it with an open mind. It not only tastes much better than expected, it has an excellent mouth feel, and makes you feel good. It helps your body to produce ketone bodies (especially if MCT oil is used). It takes advantage of how our body metabolizes dietary fat. When we consume pure fat while in a fasted state, our body will continue to function as if it is fasting. There is no insulin response. Dave Asprey markets a more refined version of MCT oil he calls Brain Octane Oil. It includes only the 8 chain fatty acids which produce ketone bodies most efficiently. I started intermittent fasting initially drinking bulletproof coffee for breakfast and lunch. I gradually transitioned back to black coffee as my body adjusted and seemed to mobilize stored energy better.
6- When breaking the fast, do not calorie restrict. Eat a proper meal at a proper pace. A large salad, some high quality meat or fish and a small serving of white rice or sweet potato. Fill your plate and enjoy your meal.
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A common misconception many people have is that people on a low-carbohydrate diet only eat meat. Although "meat only" diets have been studied, and actually have been found to be safe, this is not at all what I suggest. In fact, a well formulated low-carbohydrate diet should really be considered a low to moderate protein diet. Again, we need to strive to get the majority of our calories from fat. I will discuss healthy fats in the next article.
Proteins are made up of chains of amino acids. The process of digestion breaks ingested proteins down into amino acids. These amino acids can then be used by your body to make specific proteins needed structurally (bone, muscle) and to support cellular function via signaling and enzymatic activity.
Amino acids can also be used for energy or stored as body fat. Of the 20 amino acids used in the human body, 9 are essential. This means they must be eaten. The body can fabricate the other 11 if needed. A complete dietary protein contains all of the essential amino acids. Meat is a complete protein. Incomplete proteins can also be eaten in combination to supply all essential amino acids. This is how vegetarians can ensure proper protein intake.
The amount of protein an individual needs is based on the normal turnover of proteins in their body each day. Larger body mass and an increased activity level require increased protein intake. Eating protein beyond this point is not beneficial and could significantly undermine weight-loss efforts.
Some amino acids will cause an insulin release. As I discussed in the last blog posting, we are attempting to minimize our insulin levels to allow our body fat to be mobilized for energy, and to stop the blood sugar instability that leads to cravings. For these reasons, it is best to eat the proper amount of protein (a moderate level) for your body and activity level.
How much is that? Adequate protein intake for most people is 0.3-0.8 grams of protein per pound of ideal body weight. I often use 0.5 grams as a simple rule of thumb. So this means if your ideal body weight is 150 pounds, you should strive for about 75g of protein over the day. To maximize weight loss, especially if not exercising, aim for the lower end at about 50 grams. Some body-builders consume several times this amount of protein, but their goals are completely different than ours. We are not trying to pack on as much muscle as possible, we are trying to burn body fat for energy while maintaining our muscle mass and optimizing the function of our cells.
To put this in perspective, a six ounce steak has about 50 grams of complete protein. A five ounce serving of salmon will deliver 36 grams of protein. A single large egg or a handful of almonds each contains 6 grams of protein. One slice of cheddar cheese will provide 7 grams of protein. Vegetables also contain protein, but at a much lower concentration. As I will further develop in the future, my recommended diet is not vegetarian, but it does contain lots of vegetables. The biggest volume of food you should be eating is non-starchy vegetables, while the biggest source of calories will ultimately be dietary fats. When eaten in significant quantity, vegetables will actually end up supplying a reasonable amount of protein.
A common misconception that has been beaten into our heads is that "lean" meats are best. We have been trained to fear fat. For this reason, many people instinctively think of chicken breast, or tuna as excellent protein sources. And they are. But not for optimal body-weight, health, and performance. Why is this? Because they contain no fat. Just 3 ounces of cooked tuna supplies 25 grams of protein, but only 5 grams of fat. Even worse, a half of a chicken breast contains 27 grams of protein and just 3 grams of fat.
Remember, we want our body to burn fat, thus we must eat fat.
Take home points:
1: Low-carbohydrate does not automatically mean high protein.
2: It is easy to supply your body with adequate protein by consuming a variety of foods.
3: Don't fall into the "lean meat" trap. Lean meats over-supply protein, and under-supply fat. Choose the fattiest cuts of meat and don't feel guilty.
4: When you do choose to eat a lean meat like chicken or non-fatty fish, keep the portion size small, and feel free to add plenty of butter, cream, or olive oil to the sauce.
In the next few postings, I will break my nutritional recommendations down into a few simple steps.
First, it is important to understand that there are only 3 actual food groups. These are the macronutrients. The 3 macronutrients are fats, proteins, and carbohydrates. Each can provide our body with energy. In addition to potentially supplying energy, protein also provides the building blocks that make up the structure of our body. Technically, our body can also obtain energy when it metabolizes alcohol, but this should not make up a significant part of a healthy diet so we will exclude it for now.
Carbohydrates are sugars, starches, and fiber. Fiber is the undigestible part of plants and grains and does not provide energy to your body. Whether consumed in the form of sugar or starch, carbohydrates are all broken down, or digested, into sugars. This happens very rapidly in your gastrointestinal tract. Starch is just a long chain of sugar molecules linked together. This linkage is rapidly broken. You can test this by chewing a saltine cracker and not swallowing it. After a few minutes in your mouth the enzyme in your saliva (salivary amylase) begins breaking the starch down into sugar. This is why the chewed cracker begins tasting sweet when held in your mouth.
As far as your body is concerned, all absorbed carbohydrates are sugar.
When sugar is absorbed, your blood sugar level rises. Although some glucose (sugar) in you blood is necessary, too much is toxic. Your body responds by secreting insulin from the pancreas. This drives the sugar into your cells to provide energy. When your cells have enough supply of sugar, the excess can be stored as glycogen. Glycogen is primarily stored in the liver and muscles. We can only store about a days worth of energy in this form. When glycogen levels are adequate, excess blood sugar is then stored as body fat.
The modern diet tends to be rich in carbohydrates, especially processed, refined carbohydrates. As a result of constant exposure to incoming sugars, our body responds by increasing (up-regulating) the carbohydrate metabolizing system. Studies have suggested many people have fasting hyperinsulinemia (abnormally elevated insulin levels beyond what is needed to deal with a recent meal). This can result in 2 major issues: 1- extreme hunger, 2- inability to mobilize body fat for energy.
Since insulin lowers blood sugar, when your pancreas, in anticipation of the next carbohydrate rich meal, secretes more insulin than you require, your blood sugar will drop. This can lead to light-headedness, headaches, irritability, and extreme hunger. This leads you to seek out a carbohydrate rich meal, drink, or snack. Although the crisis is temporarily averted and you feel better, the cycle of blood sugar instability and increased resting insulin levels has been reinforced.
Assuming you are able to reduce your caloric intake to a level below what you expend in a given day, you would expect to lose weight. As I discussed previously, it is not quite that simple. Elevated insulin inactivates the enzyme necessary to mobilize stored body fat to use it for energy. So even when you eat smaller meals, or even skip meals, if your body is so used to eating a steady supply of carbohydrates and has elevated insulin levels as a result, you will not be able to burn your body fat for energy.
Although we have been led to believe that whole grains are healthy, the statistics show the opposite. We have seen constantly increasing levels of obesity, diabetes, heart disease, and dementia as people have been encouraged to consume more grains.
Lets keep step one simple. Refined carbohydrates dump a huge amount of sugar into your body. Your body responds by burning some as energy, storing the excess as fat. Continuing this process makes burning body fat for energy very difficult.
Unfortunately it is not just candy and desserts I am referring to. Bread, cereal, pasta, low-fat sweetened yogurt, rice, soy milk, fruit, and potatoes are all carbohydrates.
To initiate weight-loss we need to change our biochemistry. Our body will respond to the fuel we supply it. If we constantly supply it with carbohydrates, it will respond as I outlined above, leaving you hungry, and making sustained weight-loss nearly impossible.
I recommend eliminating all carbohydrates except those found in non-starchy vegetables as the first step to sustainable weight-loss. This will provide the added benefits I discussed previously including: no cravings, better mood, improved mental alertness, and improved physical stamina. There are a variety of potential longer-term benefits I plan on discussing in the future as well.
A few important points:
1- When beginning a low-carbohydrate diet, your body will excrete water and salt. Please drink plenty of water, and feel free to add additional salt to your meals, especially if you feel a bit light-headed. This issue generally resolves within a few weeks.
2- You may find yourself eating because it is time to eat, rather than because you are hungry. This happened to me very quickly. It is ok to skip a meal if you are not hungry. Listen to your body, it is amazing how quickly your physiology will adapt to your new diet.
3- If you become hungry, or experience cravings for carbohydrates, eat. But do not eat carbohydrates. Eat fat. Add butter to your vegetables, use heavy cream in your coffee, eat bacon, but do not eat sugar or starches. You are teaching your body to burn fat. So you need to supply it with fat to burn. You may be surprised how quickly the carbohydrate cravings stop.
4- Do not count calories or restrict portion sizes. Just skip the carbohydrates and listen to your body.
5- Eat plenty of non-starchy vegetables and high-quality meats.
Stay tuned for the next posting where I will discuss appropriate protein levels.