For most people, gaining weight is something they’d like to avoid. And yet, obesity continues to be identified as a public health crisis by the Centers for Disease Control and Prevention with almost 40% of the American adult population considered to be obese. (1) The fact is, the cause of weight gain could be something other than diet and exercise, something unexpected that may not even be on a person’s radar. To achieve sustainable weight loss, you should look at these three factors that can influence weight gain.
Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, which initiates the release of hormones and neurotransmitters to prepare the body for fight or flight. While acute stress is necessary for survival, when HPA axis activation becomes chronic, it can contribute to weight gain. (12) One key stress hormone, cortisol, is particularly troublesome because when it is chronically elevated, it may cause fat to be stored around the waistline. In one particular study, higher hair levels of cortisol were associated with higher weight and waist circumference. (3)
Also known as abdominal obesity, when someone has a higher than average waist circumference, they are at increased risk of many illnesses including heart disease and type 2 diabetes. A 2019 study showed that even non-obese individuals who had a larger waist circumference still had a higher risk of developing these illnesses. (6)
When someone is under stress there is also a tendency to eat more, choose unhealthy foods, and sleep less, all of which likely cause weight gain. (5) A vicious cycle can ensue beginning with the stress that causes increased cortisol, fat storage, poor eating habits, and lack of sleep. Consider natural sleep aids and dietary supplements that can help the body better cope with stress.
2. Hormonal imbalance
Cortisol isn’t the only hormone that can cause weight gain. An imbalance of hormones, in general, can lead to obesity. Sex hormones like estrogen, progesterone, and testosterone can all play a role in weight loss and weight gain. This can be especially frustrating for perimenopausal and menopausal women because hormonal imbalance is a hallmark of these life stages.
Estrogens help regulate metabolism and energy so when there is a rapid decline in estrogen levels, as there is with menopause, there is a corresponding reduction in metabolism and energy balance that can lead to weight gain. (4) Therefore, menopausal women who are trying to lose weight may benefit from strategies to boost metabolism including diet, exercise, and certain dietary supplements.
3. Underlying illness
Weight gain can be a sign of an underlying illness, so it’s important to rule out any potential medical causes. Here are some common diseases that can cause weight gain.
One of the medications used to treat type 2 diabetes, if it gets severe enough, is insulin. Patients are sometimes concerned that taking insulin will cause weight gain. While some patients on insulin gain weight, some lose weight as well, so taking insulin should not be a deterrent for those patients who have been deemed to need prescription insulin. (8)
An underactive thyroid has been associated with weight gain. There is a correlation between high leptin levels and hypothyroidism, which can lead to poor appetite control and increased fat storage for people who have an underactive thyroid. (10)
The development of ovarian cysts is a hormonal issue that can lead to polycystic ovary syndrome (PCOS). Insulin resistance is a common occurrence with women who have PCOS. (9) Insulin resistant cells are unable to uptake glucose (sugar) from the bloodstream to use as energy and the Neel hypothesis suggests that this excess glucose is eventually stored as adipose (fat) tissue. (2) Long-term insulin resistance can also lead to impaired insulin production, which was found to be a predictor of weight gain and adiposity in one study. (11)
Studies consistently show that inadequate sleep is associated with alterations in hormones associated with energy balance, such as ghrelin and leptin. Ghrelin stimulates appetite and hunger, while leptin signals satiety. Research indicates that in healthy individuals, ghrelin levels rise during sleep; however, in individuals with chronic insomnia, ghrelin levels were found to be significantly lower throughout the night. Without a night-time peak, this hunger hormone may rise during the day, potentially leading to excess energy intake and weight gain. (7)
The bottom line
We all know that diet and exercise can influence weight loss and weight gain. But in some cases, that’s not the whole story. Sometimes, weight gain can come from stress, hormonal imbalance, or even an undiagnosed or diagnosed illness. To achieve lasting weight loss and maintain normal body weight, you should look at all aspects of weight gain and speak to your healthcare provider to identify and address individual factors that may be influencing your body weight.
- Centers for Disease Control and Prevention. (2021). Adult obesity facts. https://www.cdc.gov/obesity/data/adult.html
- Howard, B. V., Adams-Campbell, L., Allen, C., Black, H., Passaro, M., Rodabough, R. J., Rodriguez, B. L., … & Wagenknecht, L. E. (2004). Insulin resistance and weight gain in postmenopausal women of diverse ethnic groups. International Journal of Obesity and Related Metabolic Disorders: Journal of the International Association for the Study of Obesity, 28(8), 1039–1047.
- Jackson, S. E., Kirschbaum, C., & Steptoe, A. (2017). Hair cortisol and adiposity in a population-based sample of 2,527 men and women aged 54 to 87 years. Obesity , 25(3), 539–544.
- Kozakowski, J., Gietka-Czernel, M., Leszczyńska, D., & Majos, A. (2017). Obesity in menopause – our negligence or an unfortunate inevitability? Menopause Review, 16(2), 61–65.
- Lucassen, E. A., & Cizza, G. (2012). The hypothalamic-pituitary-adrenal axis, obesity, and chronic stress exposure: Sleep and the HPA axis in obesity. Current Obesity Reports, 1(4), 208–215.
- Lukács, A., Horváth, E., Máté, Z., Szabó, A., Virág, K., Papp, M., Sándor, J., … & Paulik, E. (2019). Abdominal obesity increases metabolic risk factors in non-obese adults: A Hungarian cross-sectional study. BMC Public Health, 19(1), 1533.
- Motivala, S. J., Tomiyama, A. J., Ziegler, M., Khandrika, S., & Irwin, M. R. (2009). Nocturnal levels of ghrelin and leptin and sleep in chronic insomnia. Psychoneuroendocrinology, 34(4), 540–545.
- Naeem, N., Basit, A., Shiraz, A., Bin Zafar, A., Mustafa, N., Ali Siddique, S., & Fawwad, A. (2019). Insulin-associated weight gain in type 2 diabetes and its relation with caloric intake. Cureus, 11(7), e5275.
- Sam, S. (2007). Obesity and polycystic ovary syndrome. Obesity Management, 3(2), 69–73.
- Sanyal, D., & Raychaudhuri, M. (2016). Hypothyroidism and obesity: An intriguing link. Indian Journal of Endocrinology and Metabolism, 20(4), 554–557.
- Schwartz, M. W., Boyko, E. J., Kahn, S. E., Ravussin, E., & Bogardus, C. (1995). Reduced insulin secretion: An independent predictor of body weight gain. The Journal of Clinical Endocrinology and Metabolism, 80(5), 1571–1576.
- Scott, K. A., Melhorn, S. J., & Sakai, R. R. (2012). Effects of chronic social stress on obesity. Current Obesity Reports, 1(1), 16–25.
- Sutin, A. R., & Zonderman, A. B. (2012). Depressive symptoms are associated with weight gain among women. Psychological Medicine, 42(11), 2351–2360.