Only then will you be able to enjoy long-term ideal weight. Here, we'll take a look at the role leptin plays in all of this.
Leptin and Obesity
One of the most important hormones responsible for hunger, metabolism, reproduction, fat management and energy production is leptin. Leptin is made by fat cells in proportion to body fat mass, so more body fat means you'll be producing more leptin.
Without proper leptin response, you will not feel satisfied from your meals. In overweight people, there is an increase of fat mass and a corresponding increase in circulating leptin. In such cases the appropriate response of reducing food intake and increasing energy expenditure doesn't happen, and this suggests a state of leptin resistance. This leptin resistance results in a leptin deficiency in the hypothalamus and so multiple mechanisms are activated to increase fat stores, as the body perceives this as a state of starvation.
Inflammation in the body can inhibit leptin signaling in many different cell types and then the fat mass has to increase to produce more leptin. The inflammation can be generated by a variety of factors like processed and refined foods and sugar, gut infections, intestinal permeability, nutrient deficiencies and fatty acid imbalances.
There are actually even more serious results, which can be determined by leptin and fat accumulation. In addition to producing inflammatory hormones like leptin, visceral fat is also a factory for estrogen production. Surplus of estrogen produced by visceral fat adds considerably to breast cancer risk. In males, elevated estrogen levels will cause excessive breast development (gynecomastia).
The metabolic effects of leptin resistance include a diminished TSH secretion, a suppressed T4 to T3 conversion, an increase in reverse T3, an increase in appetite, an increase in insulin resistance and an inhibition of lipolysis (fat breakdown).
These effects of leptin resistance on thyroid hormones contribute to the drop in TSH and T3 levels that occur with dieting and results in decreased tissue thyroid action and a depressed metabolic rate that inhibits weight loss and promotes weight gain.
Starvation dieting can decrease resting metabolic rate by as much as 40%; food restriction at a level to maintain just a 10% reduction in body weight results in significantly decreased intracellular thyroid hormone levels and a diminished metabolic rate. This does not return to normal even after a normal diet is resumed. When combined with the effect of leptin resistance, this accounts for the majority of regained weight in weight reduced subjects.
There are many factors that can negatively impact leptin levels including: fructose and simple carbs consumption, overeating, lack of sleep and high stress, high insulin levels, exercising too much or too little, or doing the wrong type of exercise, grain and lectin consumption.
Diagnosing Leptin Resistance
If individuals are having difficulty losing weight, at Holtorf we recommend obtaining a metabolic panel that consists of a leptin level, TSH, free T4, free T3, reverse T3, TPO antibody, antithyroglobulin antibody, glucose, insulin, HgA1c, IGF-1, testosterone, CRP, TNF-alpha (highly sensitive), IL-6 (highly sensitive), CRP, homocystine, SHBG and lipids.
In general, a leptin level greater than 10 is associated with leptin resistance. Therefore, if it's above 10, the TSH is unreliable (artificially decreased) and a normal TSH cannot be used to rule-out significant cellular hypothyroidism. It's one more reason to rely on a comprehensive panel to correctly assess your health state.
How Can You Solve Leptin Resistance?
Decreasing the factors that cause leptin resistance and inflammation is essential, as is decreasing fat mass. In addition, it's essential to make some dietary changes like: avoiding refined foods, sugars, fructose, GMOs, industrial vegetable oils, conventional, industrial dairy and meat. Instead, rely on high quality protein and fats at all meals, coupled with lots of vegetables. Don't skip meals to keep your blood sugar balanced, get enough sleep, spend time outdoors and choose high intensity and weight lifting over cardio exercises, especially in the beginning. Also, remove environmental toxins from your life as these are a stress on your body.
There are also medications like Byetta and Symlin that can help. These can have good results if given in conjunction with other metabolic treatments and following a healthy lifestyle.
Another natural method we recommend is supplementation with Lept-N-Hance from HoltraCeuticals.
A comprehensive, integrative approach to health will find that many overweight patients have, in addition to leptin resistance, dysfunction of the hypothalamus-pituitary-thyroid axis as well as dysfunction of the cellular thyroid metabolism and utilization. Correction of these dysfunctions can result in dramatic, long term, successful weight loss.
