How much do hormone levels have to do with weight control?

Hormones are complicated and our understanding on their influence on weight management is in its infancy. We do know that high cortisol levels (usually from chronic stress) can lead to difficulties in weight loss and underlying medical conditions (including diabetes and polycystic ovarian syndrome) can influence the weight loss process. Your GP is the best point of call and if hormonal distrurbances are detected, approriate referrals will be made. The other thing to note is that weight loss can be a slow process - after all, the excess weight didn't suddenly appear overnight, but often over years so it can take just as long to lose the weight as it did to gain it. An Accredited Sports Dietitian can help, especially if you are new to exercise and having a ‘supporter’ on your team can be all the difference. http://www.sportsdietitians.com.au/findasportsdietitian 

Hormones play a part in body weight regulation and also regulating food intake. Some evidence suggests that regulation of body weight and intake occurs on both a short and long term basis. Short term regulation controls the consumption of food from meal to meal. Long term regulation is controlled by the availability of adipose or fat stores and hormone responses.
 
Short term regulation is concerned with the hormones that influence hunger, appetite and satiety (hunger suppression). Between meals when the stomach is empty, a recently identified hormone, ghrelin is released and sends a “hungry” message to the brain. This message stimulates the release of neurotransmitters or chemicals which increase hunger. As a meal is consumed, ghrelin production decreases rapidly and hunger is reduced.
 
After a meal is consumed other hormones are released which regulate the urge to eat. Cholecystokinin (CCK) a hormone which is produced in the small intestine increases during and after a meal. CCK production following a meal reduces appetite and promotes satiety (suppresses hunger). Another recently identified hormone, PYY produced in the small intestine suppresses appetite for up to 12 hours. The amount of PYY produced is proportional to the energy or the caloric content of the meal.
 
Long term regulation involves a feedback mechanism in which a signal from the adipose or fat stores promotes a reduction in hunger. Leptin, is a hormone produced by the fat cells. The more full the fat cells the more leptin it produces and sends a “satiety” message to the brain. This message then stimulates the release of neurotransmitters or chemicals which suppress hunger. The effect of leptin, then, is to control the level of stored body fat. As the level of body fat decreases, the amount of leptin produced decreases and hunger is not supressed as much. As the body fat level increases, the amount of leptin increases and energy or caloric intake is reduced. This mechanism works well in people with a healthy weight. In overweight individuals, however, this mechanism is defective as the message to the brain is not processed appropriately and as a result increased leptin levels do not suppress hunger.

However, there are many other factors that influence energy intake and body weight including:

·         Consuming more food through larger portion sizes
·         Consuming food and drink higher in energy (kilojoules or calories)
·         Being sedentary or physically inactive
·         Following restrictive weight loss or fad diets
·         Genetics
 
Successful weight management requires a life-long commitment to a healthy lifestyle, which includes eating healthy foods and keeping physically active in a way that is both sustainable and enjoyable. An Accredited Practising Dietitian can provide expert dietary advice on weight management which is tailored to indiviudal needs.

Hormones play a big role in weight management, energy and mood.  For example conditions like diabetes, insulin resistance, polycystic ovarian syndrome are affected by testosterone and insulin hormone. Body of which make it easier to gain weight and less able to lose weight. 

If you are unsure about whether you might  have one of these conditions. For example you may suspect you have insulin resistance.  It's good to just go get your hormone levels checked via a blood test by your local GP.

Hormones do play a certain role in weight control, especially for menopausal women. For post-menopausal women in particular, estrogen levels help to regulate fat metabolism and then after menopause, because estrogen levels have deceased there is less aid in fat metabolism so it does play somewhat of a role however it is not the biggest factor. The biggest factor is always how much energy comes in versus how much energy is expended out by physical activity and exercise. So while it does play a role it is not the biggest component.

There's two groups of hormones involved in weight control, hormones such as leptin which give us the filled up feeling and hunger hormones such as ghrelin, which makes us hungry. Often, morbidly obese patients have a misbalance of these hormones and bariatric surgery can be used to readdress this balance and particularly a gastric band can increase the hormones and this gastrostomy can decrease hunger hormones.

A large number of hormones are critically involved in weight control.
Majority of which involve complex feedback systems and complex interactions.

I like to think of them as being involved in energy burning or storage (carbohydrate, fat or protein metabolism, thermogenesis, basal metabolic rate), and those that control energy intake(appetite, appetite supression).

It turns out that our brain is inherently wired to want to eat. There are 9 hormones that supresses food intake and only really 1 that stimulates appetite.

There is evidence to suggest that, in fact, people stop losing weight after dieting/exercise due to changes in these hormones that make people more hungry. The body tries very hard to maintain weight principally via these hormones.

I would advise that you speak to your GP, dietitian, exercise physiologist or other health professionals if there are ongoing concerns regarding difficulty losing weight.

Regards,
Dr Kevin Lee
Consultant Physician Endocrinologist
http://www.dr-kevinlee.com

Adding a bit to what Dr Lee wrote:

A very recent paper (a collaboration between Australian and English teams) has shown that a hormone called leptin (made by fat cells) is causally linked to hypertension (which is associated with increased cardiovascular risk) in people who are morbidly obsese . People who are morbidly obsese and do not make leptin or its receptor do not have hypertension - this was backed up by animal studies.

This is at the “basic science” stage currently but with more work it may lead to improved therapy.

There is a very technical but free-access account of the paper here: http://www.cell.com/abstract/S0092-8674(14)01430-5 .