Hunger and Hormones
Hormones serve as a major form of communication between different organs and tissues in the body. They shape everyone, from our height, weight, metabolism, sleep, how we behave and how we feel. Hormones are the key.
So what hormone affects our appetite?
Leptin is a hormone made by fat tissue that acts on the brain to regulate food intake and body weight. A lack of leptin in the body signals your brain to increase food intake. Conversely, where leptin levels rise, it signals your body that you’re full, so you should stop eating.
So how can people become overweight when we have a hormone that regulates appetite?
In order for you to significantly gain weight you must first become leptin resistant. The more leptin resistant you are the more you will be able to eat before your body tells you to stop eating. Obese people exhibit significantly high concentrations of circulating leptin.
It is a similar situation to people with Type 2 diabetes who become resistant to the effect of insulin. Whilst these obese people may have high concentrations of leptin in their bodies they have become resistant to the effects of leptin so their appetite is left uncontrolled.
When your body is not affected by the satiating effects of leptin not only can you eat more but, your energy metabolism falls, causing a reduction in your body’s ability to burn fat.
Why does this happen?
There are a few reasons why we think this happens.
- Inflammation: Inflammatory signalling in the hypothalamus is likely a cause of leptin resistance
- Free Fatty acids: having elevated free fatty acids in the bloodstream may increase fat metabolites in the brain and interfere with leptin signalling
- Having high leptin levels: Higher levels of leptin help increase the risk of leptin resistance in the first place
- Consumption of high amounts of fructose. (Animals that were fed a high fructose diet put on more weight as they ate more than those fed a high-fat high -calorie diet.) Fructose stimulates weight gain through its effects on your appetite and by blocking fat burning. Fructose also changes your body composition to increase fat storage.
So what should I do?
- Avoid processed foods as they can help drive up inflammation in the gut.
- Eat Soluble fibre that will help improve gut health
- Make sure you aim to get 7-8 hours of good sleep
- Eat protein- protein rich diets have shown an increase in leptin sensitivity.
- Try and avoid the following sweeteners, table sugar, high fructose corn syrup, agave nectar, brown sugar, honey and maple syrup.
- Restrict fructose consumption to about 15-25 grams per day. Avoid fruit juices, as well as sugar drinks and yogurt drinks.
- Minimise the consumption of ripe fruits. As fruit ripens the sugar content goes up, while many of the antioxidants and other beneficial nutrients go down. (grapefruits and berries have minimal fructose and high levels of important nutrients so try and choose those)