A plain language explanation of how and why low carb diets work.
Let me start off by saying I am simplifying a lot of the biochemistry of how our bodies deal with carbs, protein and fat. However I feel it is important for people without biochemistry degrees to understand why low carb diets work. Please feel free to ask me questions in the comments.
Low carb diets work for 2 main reasons.
1. Insulin. Insulin is the hormone in your body that protects you from high levels of sugar (glucose) in your blood. When you eat carbohydrate (that convert to sugar in your body) your blood sugar rises. The body can not live when blood sugar is too high, so you pump out insulin to send that sugar either into you cells for energy or if there is excess sugar it gets converted to fat and stored.
Insulin also stores fat in your fat cells. So any fat eaten with those carbs will be store as well.
When you dramatically reduce the amount of carbs you eat your blood sugar does not spike and thus your insulin levels don’t either.
In very simplistic terms. Without insulin you can not (easily) store fat. Thus when you eat a low carb high fat diet there is not insulin around to cause you to store that fat.
2. Reduced hunger. Anyone that has tried a low fat high carb diet knows the feeling of hunger. You are always thinking about your next meal. You are eating snacks between meals to “keep your energy up”. Willpower is the name of the game. Just stop eating as much and the weight will come off. While true it is not a fun way to live life.
An amazing thing happens when you adapt to an LCHF diet. Hunger as you know it practically disappears.
A typical standard American diet (SAD) has your body on a sugar roller coaster. You eat your oatmeal and muffin for breakfast and your blood sugar skyrockets insulin rushes in and because many people are no longer perfectly sensitive to insulin your body overshoots the amount causing too much sugar to be taken out of the blood. With low blood sugar you body starts screaming for more energy, making you feel hungry. You grab an apple at 10am and the cycle starts again.
Your body does not store sugar as sugar. Thus when your primary source of energy is sugar, it comes practically exclusively from your diet. When you run out, your are out of energy and you need fool. Now!
LCHF is different. When eating LCHF and fully “keto adapted” your body uses ketones as its primary energy source. Ketones are produced in your body by breaking down fat. Ketones can be used in basically the same way as glucose to fuel your body. The main difference is your body can store fat. Unfortunately on most of us we have store far too much of the stuff.
So let’s return to breakfast. Say you eat a egg with a couple slices of bacon and have a bullet proof coffee with 2-4 tbs of fat. This meal does not cause a spike in blood sugar. There is no insulin response. No spike. No crash. Your body goes about digesting the fat and converting it to ketones. You are in a state of ketosis. When your meal is digested your body simple switch to burning the fat it has stored before. There is no energy crisis and no crazy emergency hunger response.
Your body simply runs off the stored fat.
This reduces the desire for snacking and as a result can naturally limit the amount of food you eat. Reducing your calorie intake without willpower.
From a high level it really is that simple. Without insulin you can’t store fat and burn mor fat. Without hunger you eat less and feel better.
There are a lot of intricacies to a LCHF lifestyle and a lot of reasons they work differently for different people. Over the next few weeks I will explain much of that. However the basics are critical to understand. Please let me know if you have any questions or if I have over simplified things to the point of being wrong. I love answering question and enjoy lively discussion.