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Key points
- Most people struggle with weight loss or experience weight regain after dieting.
- Persistent inflammation may be the secret behind the challenge of weight loss.
- Anti-inflammatory approaches are novel strategies to address challenges with weight loss.
I was watching a newly colorized documentary film about the streets of New York from the 1930s. The film depicted individuals like us who are mostly absent nowadays. One of the film's main highlights that intrigued me was how fit the characters were in the film. Since the last decades of the 20th century, obesity has been steadily increasing up to the present day. Obesity today is considered a pandemic due to the availability of cheap, calorie-dense food and a sedentary lifestyle. An increase in obesity is correlated with the prevalence of several related diseases, including type 2 diabetes, hypertension, imbalances in serum lipids such as cholesterol and triglycerides, and certain types of cancers. Obesity is also associated with low to moderate systemic inflammation.
Nowadays, the common treatment for weight management includes calorie-restricted diets and programs that promote increased physical activity. Most obese individuals end up regaining the weight they have lost. A study revealed that more than 50 percent of lost weight is regained within two years, and more than 80 percent is regained within five years. As a result, many people now view weight loss as a futile effort. They find it challenging to achieve their ideal body weight easily. Some individuals may find it challenging to lose weight and struggle to maintain their weight-loss regimens. Weight regain is also observed in surgeries that remove excess fat tissue, such as bariatric surgery. Struggling with weight loss and then regaining it is known as the yo-yo effect.
Persistent inflammation may impair weight loss and promote weight regain during dieting.
Inflammation is typically a physiological response of the immune system to infections and tissue damage. Although inflammation is typically resolved in the late stage of the immune response under normal conditions, in chronic states, inflammation persists as the immune system continues to send inflammatory cells and compounds. Sustained inflammatory conditions in the long term impair the normal functions of tissues and lead to several illnesses. Inflammation has a major role in metabolism dysregulation and obesity-related insulin dysfunction.
It has been shown that after weight loss, adipose tissue undergoes size reduction, cellular shrinkage, and mechanical stress, which can lead to inflammation. After low-calorie diets, fat tissue has insufficient energy to support extracellular cellular matrix remodeling mechanisms needed to adapt to the new size. Consequently, mechanical tension arises between cells. Also, some evidence shows that inflammatory markers persist in the plasma even after weight loss following a calorie-restricted diet or bariatric surgery for at least 3 to 9 months. Individuals with sustained inflammatory compounds and immune cells in their blood are more prone to weight regain after losing weight.1
How can we get rid of the yo-yo effect?
Persistent inflammation after weight loss appears to be a key factor contributing to the challenge of weight regain. Several strategies are proposed to prevent chronic inflammation during weight loss. Omega-3 polyunsaturated fatty acids are suggested to have anti-inflammatory properties and may be useful in combination with dieting or surgery. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are abundant in cold-water fish such as salmon and sardines, are more important. They are precursors of compounds that play a significant role in the resolution stages of inflammation.
Some supplements, such as conjugated linoleic acid, are proposed to increase heat production in fat tissue. However, there is not sufficient evidence to support their role in inhibiting chronic inflammation during weight loss. Also, some anti-inflammatory drugs are being tested in combination with diet and weight loss surgery. Regular exercise is a well-known strategy to prevent inflammation when combined with calorie-restricted diets.
Microbiome imbalance may contribute to post-dieting weight regain.
Obesity alters the microbiome population, also known as symbiosis, in the gut. Sustained obesity-induced microbiome signature after successful dieting in mice prompts us to consider the role of beneficial probiotic supplements in a weight loss management program.2 This study highlights the potential role of the gut microbiome in weight management and sheds light on the complexity of factors influencing post-dieting weight maintenance. Since there is evidence indicating that the microbiome of lean individuals can promote weight loss in obese individuals, it appears that targeting the microbiome could be beneficial for managing weight in obese individuals. Additionally, the gut microbiome and its metabolites can modulate inflammatory responses, affecting both intestinal immunity and distal inflammation. Factors such as diet, probiotics, prebiotics, and microbiome-based therapeutics can impact weight management.3 As a safe medication, probiotic supplementation with beneficial microbes may help reduce chronic inflammation following dieting and bariatric surgery.
References
1. van Baak, M. A., & Mariman, E. C. M. (2019). Mechanisms of weight regain after weight loss—the role of adipose tissue. Nat Rev Endocrinol, 15(5), 274–287. doi: 10.1038/s41574-018-0148-4
2. Thaiss, C. A., Itav, S., Rothschild, D., Meijer, M. T., Levy, M., Moresi, C., . . . Elinav, E. (2016). Persistent microbiome alterations modulate the rate of post-dieting weight regain. Nature, 540(7634), 544–551. doi: 10.1038/nature20796
3. Clemente, J. C., Manasson, J., & Scher, J. U. (2018). The role of the gut microbiome in systemic inflammatory disease. BMJ, 360, j5145. doi: 10.1136/bmj.j5145
