If losing weight was so easy, we'd all look like models. But this isn't the case, and as many of us know, losing weight is hard work. 

One of the things that makes losing weight so difficult is that diets such as calories-in and calories-out oversimplify the efforts needed for sustainable weight loss. 

Weight loss and weight maintenance involves many complex processes in the body such as fluctuating levels of hormones, optimal calorie intake for one's body mass, and modulating things such as systemic inflammation.

There is no denying that calories play a central role in weight gain or loss. For years, the notion of a calorie deficit was necessary for losing weight - that is, expending more calories than one consumes. 

This is true, but only partly, and is why focusing solely on calorie-in and calorie-out can keep one from achieving his or her target weight.

By looking at the bigger picture, it’s not only the calories that determine whether someone will lose weight. In fact, a number of physiological processes and an interplay of hormones, internal energy expenditure and inflammation all play important roles.

Going beyond that “calorie-calculation” makes perfect sense when you try to answer a common question - why do so many people never gain weight no matter what they eat or how often?

We probably all have that friend who can eat whatever they want without ever gaining weight (I'm talking cheeseburger after cheeseburger here with sugar-coated donuts for dessert). 

The answer is not apparent, but by looking at the bigger picture and taking into consideration some other things with the calorie theory such as hormones and inflammation, we can gain a better understanding.

Hormones are powerful messengers in the body that play important roles in tissue growth, metabolism, reproduction, and more. Of the thousands of hormones in the human body, here are four that have the biggest influence on body weight. 

1. Insulin

Insulin is one of the most potent hormones responsible for energy balance and carbohydrate metabolism in the body. The beta cells of the pancreas secrete insulin into the bloodstream after eating. This insulin helps trigger the uptake of nutrients such as glucose into the cells of the body.

Many people who are overweight, but consume low calories and spend hours in the gym might not be able to shed pounds because of a condition called insulin resistance (IR). IR reduces the sensitivity of the cells to blood insulin.

Simply put, the cells are no longer able to utilize insulin and absorb glucose for cellular energy production. This may cause the excess glucose to be converted to fat, and stored as adipose tissue throughout the body. 

2. Leptin

Leptin, also known as the satiety hormone, is produced by fat cells and functions to suppress hunger. Those who are overweight or obese have more fat cells, which means they secrete more of this hormone.

Interestingly, many overweight individuals also eat more, which sounds counterintuitive to what this hormone does. This happens because of a condition called leptin resistance (LR). People with LR have high levels of the satiety hormone but end up eating more. This happens because cells in the body become resistant to available leptin in the body.

As a result, weight-loss efforts are severely affected.

LR can promote weight gain in three ways. First, it tricks the brain into believing that the body needs more food despite having enough calories. Second, it slows down the metabolic processes and thus reduces energy expenditure. Third, it activates the reward system in the brain thereby making the brain feel like eating is a more rewarding activity than humans are evolutionarily predisposed to feel.

3. Ghrelin

Unlike leptin, ghrelin increases hunger. Having high blood levels of this hunger hormone can significantly increase one's food intake. Normally, overweight and obese people have low ghrelin levels. However, a high-fat diet or chronic sleep deprivation can cause a considerable increase in ghrelin secretion and thus increase the risk of obesity.

4. Cortisol

Lastly, cortisol, also known as the stress hormone, is a glucocorticoid that boosts blood glucose levels and energy utilization by the brain.

While a short burst of cortisol prepares your body for a real or perceived threat through sympathetic nervous system mechanisms, chronic levels of cortisol, even in the absence of a real threat, poses a number of health risks.

One of these health risks is obesity, and this ties into why some people overeat when they're stressed. Chronically elevated cortisol can increase the risk factors for obesity, such as insulin resistance, leptin resistance, and systemic inflammation.

Studies have shown that high cortisol can reduce the activity of insulin-secreting beta cells of the pancreas. In addition, chronic stress can promote inflammation by increasing the levels of inflammatory markers.

In fact, a 2012 study found that older adults who are bereaved due to the death of a spouse or loved one typically present with higher levels of inflammatory markers than their nonbereaved counterparts.

Key Takeaway

Weight loss is not as simple as calorie-in and calorie-out. A number of hormonal, genetic and environmental factors play crucial roles. Moreover, there is no one-size-fits-all calorie theory that can be equally beneficial for one person.  

There are, however, some simple techniques to achieve sustainable weight loss, which are explained in more depth below. 

Nowadays there's more information than ever available online, with new "quick tricks" to lose weight fast, as well as a million different diets. 

The reality is that for most people, these bogus tips or obscure diets do more harm than good. Take for example the "watermelon diet", a diet consistenting almost entirely of watermelon that has been touted as a "weight loss miracle". 

Diets like these that focus on one specific food group aren't sustainable, and they deprive the body of the nutrients it needs from a variety of different foods. 

That being said, here are three no-nonsense and simple tips for sustainable weight loss:

1. Eat More Fiber

Eating more fiber will help your body feel fuller longer as it takes longer to break down in the stomach and intestines. Fiber is plentily found in all sorts of vegetables, fruits, and grains. 

2. Consume Meals with Diverse Nutrients

Meals that are prepared to contain healthy amounts of the three macronutrients (carbs, fats, and proteins) work to keep you satiated for longer due to the stimulation of special chemoreceptors lining the small intestine. These chemoreceptors signal to the stomach and brain that the body is receiving sufficient nutrients, and will help stimulate leptin release. 

3. If You're Going to cut Calories, Start Small

Cutting a drastic amount of calories consumed in the day is a sure-fire way to reduce your energy expenditure, and to slow down your metabolism. When energy levels decrease, you'll feel less likely to make what's known as "discretionary" movements, such as maintaining proper posture, walking more throughout the day, and even doing small household tasks like cleaning. This decrease in physical activity results in fewer calories burned. 

Instead, start with a small calorie deficit of around 100-200 calories a day for more sustainable weight loss that doesn't leave you feeling drained. 

Looking for a bit of extra help on your weight-loss journey? 

Lumen Naturals offers a variety of herbal supplements to help you get started, such as forskolin, garcinia cambogia, green coffee bean extract and more!

References

1. Myers Jr, M. G., Leibel, R. L., Seeley, R. J., & Schwartz, M. W. (2010). Obesity and leptin resistance: distinguishing cause from effect. Trends in Endocrinology & Metabolism, 21(11), 643-651.

2. Klok, M. D., Jakobsdottir, S., & Drent, M. L. (2007). The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review. Obesity reviews, 8(1), 21-34.

3. Iikuni, N., Lam, K., Queenie, L., Lu, L., Matarese, G., & Cava, A. L. (2008). Leptin and inflammation. Current immunology reviews, 4(2), 70-79.

4. Holmäng, A., & Björntorp, P. (1992). The effects of cortisol on insulin sensitivity in muscle. Acta Physiologica Scandinavica, 144(4), 425-431.

5. Slavich, G. M., & Irwin, M. R. (2014). From stress to inflammation and major depressive disorder: a social signal transduction theory of depression. Psychological bulletin, 140(3), 774.

6. Chen, L., Chen, R., Wang, H., & Liang, F. (2015). Mechanisms linking inflammation to insulin resistance. International journal of endocrinology, 2015.