When it comes to weight loss, it seems that losing excess weight is only part of struggle. According to researchers at the Penn State College of Medicine in the US, only one in six people who have ever been overweight or obese loses the weight and maintains the weight loss over the long term. Recent research on the hormone leptin may be the key to changing these numbers. Produced by fat tissue, leptin speeds up the metabolism and plays a central role in appetite control by acting directly on the brain's hypothalamus to signal satiety.
In overweight people, because of chronic inflammation, the leptin produced by the body does not work properly, making the processes of weight loss and weight maintenance much more difficult. Increased consumption of phytonutrients helps fight the inflammation that causes leptin resistance. Two types of phytonutrients commonly found in fruits and vegetables are carotenoids and flavonoids. These fat-soluble compounds work to reduce the inflammation that blocks leptin.
Bright, colourful foods such as cherries, pomegranate, blueberries, citrus fruits and purple grapes contain the most flavonoids, but they can also be found in dark chocolate, onions and green tea. Foods such as tomatoes, broccoli, carrots, papaya and winter squash are rich in carotenoids.
Researchers at Harvard Medical School have found that chronic inflammation leads to elevated levels of SOCS (suppressors of cytokine signalling) proteins, which block the signals that leptin sends to the brain. In addition to phytonutrients, increased consumption of omega-3 fats is also necessary to reduce chronic inflammation and unlock the leptin hormone. Because these "good fats" cannot be produce naturally by the body, they must be consumed.
It is best to obtain omega-3 fats from food to fully benefit from its natural inflammation-fighting qualities. Omega-3 fatty acids are part of leafy green vegetables, fish, seeds, walnuts and legumes such as navy beans, kidney beans and soya beans. Fish such as salmon and tuna are also rich in omega-3 fats.
While unlocking the leptin hormone is crucial for long-term weight loss, it requires a change of mindset. Food manufacturers use excess salt and sugar to combat the bland taste of artificial food and these flavours have become stapes of the British diet, overpowering more subtle natural flavours. Though less caloric than junk food, even "diet foods" rely on artificial flavours, sugar substitutes and fake fats; they do not contain the anti-inflammation properties of natural foods.
Ultimately, unlocking the leptin hormone requires avoiding both diet and junk food and increasing consumption of natural foods seasoned with natural herbs and spices.