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.