Weight loss is one of the most common health goals that women seek. The desire to change the body stems from cultural ideals about women’s beauty, but often is rooted in wanting to feel better and optimize health as we get older. Excess weight affects hormone balance, disease risk, mobility and quality of life. 

If you want to lose weight, you are not alone. And it isn’t as straight forward as we’ve been led to believe. The messages of eating less and exercising more, largely don’t work for women, especially as we get into our 40s, 50s and beyond. We need to take a deeper look at how to support the root causes of the lifestyle and hormonal pieces that are signaling the body to hold on to weight. 

Keep reading to learn more about:

• The definition of obesity
• Obesity rates in the United States
• Factors that contribute to weight gain
• The connection between excess weight and various hormones 

Then, stay tuned for Part 2 of this blog series where I will discuss the functional medicine approach to weight loss. 

Let’s jump in! 

Obesity – Definition And Prevalence 

What is obesity? Current definitions are based on the body mass index or BMI, which is an index of height to weight. A normal BMI is defined as between 18.5 and 24.9. A BMI between 25 and 30 is considered overweight and above 30 is considered obese. Morbid obesity, or severe obesity, is considered a BMI of 40 or higher. 

You can calculate your BMI here. 

We know that BMI isn’t the whole story and doesn’t tell us about a person’s frame size or muscle mass, and it certainly doesn’t convey a persons whole health story, but it’s a starting place for assessment. Your functional medicine doctor or nurse practitioner will help you put this number into context for you and look at the whole picture. 

The obesity rate in America is on the rise. In 2017-2018, the obesity rate in the U.S. was over 42 percent of adults, which was an increase of about 12 percent since the year 2000. If we consider adults who are overweight and obese, it is over 70 percent. Rates are rising in children as well. 

The cost of this obesity epidemic costs the health care over $147 billion per year as obesity raises risks for diabetes, heart disease and cancer. 

Obesity and Hormones – How Diet Affects Both

Increasing obesity rates are largely due to lifestyle factors including:

• Diet high in processed and refined food that provides excess calories but little nutrition. Lack of access to healthy and affordable food is a factor. Less than 1 in 10 Americans eat the recommended daily servings of vegetables, as an example. 

• Sedentary lifestyle that includes sitting, screen time, commuting and lack of exercise. 

• High levels of stress we face in our modern world. 

• Insufficient sleep. 

• Exposure to toxins in the air, water and food. 

All these lifestyle factors change hormone levels, that send important messages in the body about metabolism. When the hormones become imbalance, it drives weight gain and may inhibit weight loss. In some cases, it is hard to know what came first, the hormone imbalance or the weight gain. If you feel frustrated by this chicken or egg scenario let me please assure you, you’re alone nor is this necessarily your “fault.”

Here are some examples:

• Insulin. High blood sugar over time creates insulin resistance and eventually metabolic syndrome and diabetes. It is very hard to lose weight without addressing insulin resistance. While low carb diets are the rage for managing insulin resistance, they aren’t actually the ideal way to optimize insulin function long-term.

• Thyroid hormone. The thyroid gland is an important endocrine center for metabolic health. Low thyroid hormone drives low thyroid symptoms including weight gain. Conversely, obesity is a risk factor for hypothyroidism and Hashimoto’s and preventing obesity helps to prevent thyroid disease.  And unfortunately, a prolonged low carb dietary pattern (or any fad diet) raises cortisol which not only increases weight loss resistance but it may lower thyroid function too.

• Cortisol. The HPA-axis and cortisol levels help to regulate energy balance, including food intake and energy expenditure. High levels of cortisol, from being in a stressed state, increases the consumption of high fat, high sugar processed food. If you carry extra weight around the midsection, it may be related to cortisol. 

• Ghrelin and leptin. Ghrelin hormone is known as the “hunger hormone” and leptin is known as the “satiety hormone.” Both are important for energy balance and metabolic health. Lifestyle factors and obesity disrupt signaling creating ghrelin and leptin resistance. 

As you can see, hormones are running the show when it comes to weight and metabolism. A healthy lifestyle helps to create and maintain hormonal balance, but we may need additional hormone support to begin to lose weight. I’ll dive into this more in Part 2 of this article series.  

References

1. Centers for Disease Control and Prevention. Defining Adult Overweight and Obesity. Accessed 10/6/21 at https://www.cdc.gov/obesity/adult/defining.html 
2. Centers for Disease Control and Prevention. Adult Obesity Facts. Accessed 10/6/21 at https://www.cdc.gov/obesity/data/adult.html 
3. Centers for Disease Contril and Prevention. Why it matters: Obesity is common, serious, costly. Accessed 10/6/21 at: https://www.cdc.gov/obesity/about-obesity/why-it-matters.html 
4. Lebovitz H. E. (2001). Insulin resistance: definition and consequences. Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association, 109 Suppl 2, S135–S148. Abstract: https://pubmed.ncbi.nlm.nih.gov/11460565/ 
5. Song, R. H., Wang, B., Yao, Q. M., Li, Q., Jia, X., & Zhang, J. A. (2019). The Impact of Obesity on Thyroid Autoimmunity and Dysfunction: A Systematic Review and Meta-Analysis. Frontiers in immunology, 10, 2349. Full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6797838/ 
6. Hewagalamulage, S. D., Lee, T. K., Clarke, I. J., & Henry, B. A. (2016). Stress, cortisol, and obesity: a role for cortisol responsiveness in identifying individuals prone to obesity. Domestic animal endocrinology, 56 Suppl, S112–S120. Abstract: https://pubmed.ncbi.nlm.nih.gov/27345309/ 
7. Cui, H., López, M., & Rahmouni, K. (2017). The cellular and molecular bases of leptin and ghrelin resistance in obesity. Nature reviews. Endocrinology, 13(6), 338–351. Abstract: https://pubmed.ncbi.nlm.nih.gov/28232667/