Weight Management is not about calories in and calories out. It can be far more complicated. Two hormones that play a crucial role in controlling when we eat but also when we don't are Ghrelin and Leptin. Working together they tell us when we're hungry and when we're not. Each are controlled by a variety of physical and psychological factors.   
German researchers have suggested that ghrelin levels play a big role in determining how quickly hunger comes back after we eat. Normally, ghrelin levels go up dramatically before you eat; this signals hunger. They then go down for about three hours after the meal.
But some researchers believe that ghrelin is not as important in determining appetite as once thought. They think that its role in regulating body weight may actually be a more complex process.
What We Know About Leptin -- the appetite suppressor -- appears to be the bigger player in our bodies' energy balance. Some researchers think that leptin helps regulate ghrelin.
Leptin helps signal the brain that the body has enough energy stores such as body fat. But many obese people don't respond to leptin's signals even though they have higher levels of leptin.
In general, the more fat you have, the more leptin is in your blood. But the level varies depending on many factors, including when you last ate and your sleep patterns.
A study showed that rats that were given doses of leptin ended up eating less, but this effect lasted only about two weeks. It seems that the rats developed a resistance to leptin's appetite-cutting effects.
How to Control Hunger HormonesAre there ways to control our "hunger hormones," and thus rein in our appetites? Possibly -- by avoiding high-fat foods.
When we eat, messages go out to various parts of our bodies to tell us we've had enough. But when we eat fatty meals, this system doesn't work as well, says Dallman. Eating fat tends to lead to eating more calories, gaining weight, and storing fat, Dallman says. Researchers have seen some of these effects after only three days of a high-fat diet.
But researchers have shown that either a diet rich in either "good" carbohydrates (like whole grains) or a diet high in protein suppresses ghrelin more effectively than a diet high in fat.
Something that might help (and certainly won't hurt) is to get enough sleep! In a study of 12 young men, sleep deprivation was associated with an increase in ghrelin levels, appetite, and hunger compared with when they slept 10 hours a night.
All in all, this adds to the huge amount of evidence showing that avoiding a high-fat diet is one of the keys to maintaining a healthy weight.
Leptin inhibits ghrelin in two ways; it reduces ghrelin secretion by gastric cells, and suppresses the expression of ghrelin receptors in the NPY system, therefore preventing the stimulation of feeding behaviors by the latter. This effect is postulated to constitute the major feedback loop between the organs of eating and the hypothalamus which maintains body weight.
When this loop is disrupted at any point, either in terms of timing, duration, or magnitude of feedback impulse signalling, hypothalamic loss of feeding is lost, resulting in obesity. Leptin also increases the rate of thermogenesis and thus promotes weight maintenance.
Ghrelin, on the other hand, stimulates feeding and results in obesity. It is produced in the stomach and also in the hypothalamic subparaventricular zone, which has an appetite-stimulant action. Ghrelin levels rises before a meal, and goes down after meals.
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Moreover, ghrelin levels fluctuate in accordance with changes in energy reserves in the body. Thus ghrelin is episodic in secretion, but the amplitude depends upon the feeding status. This hormone is also involved in the short-term regulation of human appetite.
Experimentally, even when the same type of diet is fed to different rodents, two categories are rapidly formed: the first is obesity-prone and starts to put on weight rapidly, whereas the second group shows a static weight. This can be explained by the fact that the first group alone shows high leptin levels, with low ghrelin levels, possibly caused by the former. Conversely, the other group has no alteration in the secretion of both hormones.
Hypothalamic Restraint by LeptinIn another study, leptin lowering was associated with high levels of ghrelin secretion, but there was a centrally-operating suppression of the expected appetite drive despite increased ghrelin. Ghrelin secreted in the stomach mucosa circulates to the brain and crosses the blood-brain-barrier. It acts together with locally secreted ghrelin in the hypothalamus to stimulate the NPY and other neurons in the ARC-PVN nucleus to stimulate appetite. This can be inhibited by Y1 receptor antagonists acting on the NPY neurons.
Leptin acts to reduce the synthesis, release, and biological actions of NPY in the ARC-PVN neuronal system via long leptin receptor activation. Yet leptinopenic mice (i.e. those with low levels of leptin) failed to develop a good appetite, though their ghrelin levels rose. Thus the hypothalamic restraint exercised by leptin overrides even a strong peripheral afferent signal by ghrelin.
Actions of GhrelinThere are several notable actions that ghrelin has on a human body:

• It regulates the blood glucose levels through reduced insulin secretion and by regulating the synthesis and breakdown of glucose and glycogen
• It reduces heat production to conserve energy
• It reduces sympathetic activity
• It promotes the differentiation and fusion of muscle fibers
• It plays a role in regulating bone growth through osteoblast differentiation and proliferation, a role in bone protection, and has an opposing role to leptin in bone metabolism
• It is also highly expressed in metastatic cancer cells

When the body is in positive energy balance, ghrelin levels go down, and vice versa in cases of fasting or anorexia nervosa. Leptin does exactly the opposite; however, it is not clear whether the primary stimulus is the calorie deprivation or the lower energy stores.
In the anorexic eating disorders, the ghrelin levels are chronically raised, which may be due to the negative state of the body’s energy, and are meant to stimulate the appetite to increase body fat percentage. Nevertheless, it may also mean that such patients are unresponsive to ghrelin.

Don’t feel bad if you’re confused about nitrates and nitrites in food. Are they good, bad, or something else? Unless you majored in chemistry, some uncertainty is understandable. They certainly sound similar. But rest assured there are differences between these compounds.

​Nitrates are fairly simple molecules consisting of one nitrogen atom bound to three oxygen atoms. The chemical formula for nitrate is NO3. Nitrite is a molecule that consists of one nitrogen atom bonded with two oxygen atoms: NO2. To further confuse the issue, nitric oxide, which occurs naturally in the body, consists of one nitrogen bonded with one oxygen. This simple gaseous molecule is represented as: NO.
To be clear, NO is good for you. Indeed, it’s crucial. The body uses NO to signal your blood vessels to relax. This helps promote lower blood pressure, and even plays an important role in healthy sexual function.
The Good and The Bad Nitric Oxide (NO)NO is a key signaling molecule. When released by the blood vessels themselves, it signals blood vessel muscle cells to relax. This, in turn, lowers blood pressure. That’s important, because high blood pressure (hypertension) is one of the most common and dangerous risk factors for cardiovascular disease.
Hypertension is often linked to atherosclerosis, the underlying process of inflammation and plaque buildup that accompanies the stiffening and narrowing of blood vessels. Atherosclerosis tends to be a long-term, progressive process.
Some people with atherosclerosis may eventually experience heart attack or stroke. In most cases, they will have experienced hypertension, often for years, as the heart struggles to compensate for partially clogged blood vessels, dysfunction in the endothelium (the tissue lining the interior of blood vessels), and restricted blood flow. Having adequate supplies of NO on hand helps the blood vessels function properly, and may significantly reduce blood pressure.
Nitrates: (NO3) And that’s where nitrates (NO3) come in. Dietary nitrates are compounds primarily found in whole plant foods, such as beets and dark green leafy vegetables which supply the raw material the body needs to produce NO. Research shows that people who consume greater amounts of these foods tend to have higher levels of NO,and lower blood pressure.
They also enjoy a certain amount of protection against cardiovascular disease. For example, some intriguing small studies have shown that drinking raw beet juice every day may be linked to significant reductions in blood pressure among people with mild hypertension. 
The evidence is clear: consuming dietary nitrates through the diet is good for cardiovascular health. Thus both NO and NO3 are good for you.
Nitrites: (NO2) Nitrites (NO2) have gained a bad rap because they are routinely used to cure deli meats. They are added to products such as bacon, for instance, to preserve the meat’s “healthy” red or pink color. Left untreated, bacon and other cured meats tend to oxidize and turn an unappetizing shade of gray.
Sodium nitrite is a salt of nitrite that has been used for this purpose for centuries. Although sodium nitrite is not inherently toxic, problems can arise when this chemical reacts with amino acids in the meat itself,especially during cooking. This reaction can form chemicals called nitrosamines.
Nitrosamines are carcinogenic, meaning they have been linked to the promotion of cancer. Research has repeatedly shown that people who eat more processed, cured, and deli-type meats are at greater risk for cancer. Although it is not entirely clear how much of this additional risk may be attributed to nitrite preservatives in processed meats, it is certain that nitrosamines are occasionally formed during cooking. And they are not healthful. Nitrosamines occur in tobacco smoke, for example, and are considered a chief carcinogen associated with exposure to smoke.
 Summary: Nitrate containing compounds are necessary for survival. Dietary nitrates, primarily from plant foods, are linked to better cardiovascular health, because they provide the body with the material it needs to produce a steady supply of nitric oxide (NO). NO signals blood vessels to relax, lowering blood pressure.

In my thirty years as a clinical nutritionist I have come to realize that maintaining health and avoiding disease have three main components. I'm not saying that these are the only things that keep you from getting sick but they are crucial in keeping healthy and overcoming illness. The three work synergistically with each other and should be the foundation of living well.  What are these cornerstones of health? 
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                                                           Diet/Nutrition
                                                        Lifestyle
                                                     Environment

Diet/Nutrition;
Eating healthy can be very confusing. There are many competing theories concerning what is a healthy diet. Are carbohydrates good for you, Should you be consuming meat, Is dairy as bad as they say, What about lignans, Should you be taking supplements? These are just a few of the questions people have about diet. Dr. Mark Hymen wrote a book titled "Food" which I highly recommend. In my book, "Our Modern Mortal Trinity" I also discuss how to eat healthy based on current scientific literature. A healthy diet should balance hormones, clean your microbiome, lessen inflammation, increase immunity, help detox, increase energy, maintain healthy weight among many other health benefits. 

Lifestyle;
Smoking, Stress, Physical Activity, Balance, Flexibility, Anxiety/Depression, Alcohol/ Drug Abuse, Sleep, Weight are all aspects of your lifestyle that need to addressed to maintain a healthy lifestyle.

Environment;
Your environment is literally killing you.  Everyday, thousands of toxic chemicals enter your body via the breath you take, the food you eat, and through your skin.  These toxins affect every organ, tissue, and biological process that occurs in your body.  Today there is no place on earth in which environmental toxins have not seeped. Chemical Exposures, Dry Cleaning Agents, Skin and Hair Products, Heavy Metals, Water Toxins, Pesticides/Herbicides, Dental Work all contribute to Chronic Disease. 

     To Learn More About Diet, Lifestyle and Environment and Chronic Disease Visit;
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