The effect of leptin on weight loss
A diet high in sugar is very addictive. We have a hormone in our brain called leptin. It is secreted from fat cells that help to regulate body weight. The name leptin is derived from the Greek word “leptos” meaning thin. The hormone helps us to maintain our normal weight. It doesn’t affect food intake from meal to meal, but instead alters food intake and controls energy expenditure over time.
When we lose weight the levels of the hormone fall. This stimulates a great appetite and increased food intake. Leptin levels increase with increased body fat. Obese people have unusually high amounts of leptin. This is because in some obese people the brain does not respond to leptin so they keep eating despite adequate fat stores (leptin resistance). This causes the fat cells to produce even more fat storage.
It is like a thermostat, it reads the temperature in the house. If it is too hot it turns the temperature down and if it is too cold it turns the temperature up.
Sugar can negatively affect leptin. Insulin tells your fat cells to store energy (leading to weight gain). This energy will turn into fatty acid and triglycerides and then the fat cells build leptin. But too much insulin can stop leptin from doing its job to keep us feeling full. This will lead to overeating and obesity.
But the question is, what produced the insulin? Why is so many people’s insulin 2 – 4 times higher than 40 years ago? Leptin resistance isn’t the problem, it is the symptom and that’s where the sugar comes in.
Simple carbohydrate, starchy food (potato, pasta, bread, biscuits, and cake) is synthesised into glucose, a form of sugar which can be used from any cell in your body and only 20% will end up in your liver.
Fructose is the sweet stuff, which is the sugar we crave and get addicted to. You find it in fruit juice, soft drinks, lollies, cordials, sugar and syrup. It cannot be used from any other cell than the liver cell.
All sugars will raise your insulin level, but when the liver is overwhelmed with metabolising fructose, which will happen very easily, the excess fructose will be synthesized into liver fat. This process is called lipogenesis. It is how you turn sugar into fat. It can be the start not only of fat in the liver but also the liver releasing triglycerides into the blood stream, which can lead to hardening of the arteries, obesity, inflammation and on-going disease.
The pancreas has to produce extra insulin to do its job. If you have high insulin levels everywhere, you gain weight. The insulin is blocking the leptin in your brain, making you even more hungry.
You are in the middle of a vicious circle of wanting to consume more sugar and developing disease.
Don’t go cold turkey straight away
Strip out your sugars gently and slowly
Introduce more wholesome foods
Introduce intermittent fasting, which will control your blood sugar levels
When you snack, replace the chocolate or biscuit with nuts
When you are hungry you don’t necessarily have to eat. Often a glass of water or a herbal tea is just fine
Be clear of your motivations
Understanding your beliefs around food and eating is very helpful (for example “I need a yogurt before I go to bed otherwise I will be hungry at night” “I need a coffee in the morning otherwise it’s not a good start of the day”)
If you would like to finally lose the weight you always wanted, feeling energised and healthy, please get in touch.