Our experiences in childhood shape our decisions, our personalities, our relationships, and… our bodies? While the first three aspects of our past seem clearly to influence our present, the correlation between childhood experiences and adulthood weight gain might not be as obvious. Nonetheless, these experiences in early life can affect factors such as psychological health, cortisol regulation, gut microbiome, sleep quality, and inflammation, all of which may lead to weight gain years later.

Toxic Stress from Adverse Childhood Experiences
The most negative adverse childhood experiences (ACEs) include all forms of abuse, neglect, parental mental illness and substance use, death, divorce, incarceration, and violence, according to the CDC (1). These eight factors all lead to toxic stress, though less extreme experiences such as moving frequently, living in an under-resourced community, or food insecurity can also be sources. In fact, any prolonged period of adversity without adequate adult support can be harmful (2). This harm (in the form of toxic stress) affects both mind and body, leading to increased risk of chronic illness, all of the leading causes of death, and the focus of this article: obesity.
Toxic Stress Leads to Obesity
Toxic stress strongly affects the hypothalamus-pituitary-adrenal (HPA) axis. The HPA-axis is a critical player in the body’s ability to maintain basal homeostasis and to respond to stress (3). It regulates levels of cortisol in the body, which plays a role in memory, emotion, learning, inflammatory response, and the storage and utilization of glucose as easy energy to fuel the fight-or-flight response (4,17). After short periods of very high stress (traumatic events), or longer periods of moderate to high stress (chronic stress), the body begins to adapt to the continually increased levels of cortisol in a few key ways that are all precursors to obesity (4).
Stress-Induced Cortisol Dysregulation
Disrupted levels of cortisol lead to the accumulation of fat in adipose tissue, especially in central (abdominal) adipose tissue (5). Further, cortisol affects mood and emotion, which can increase appetite, including increasing cravings for foods high in sugar and fat. This craving occurs in part to fuel glucose metabolism that creates quick energy for the fight-or-flight response (5). This can lead to unhealthy behaviors to deal with chronic stress, such as patterns of eating high-caloric (sugary and fatty) foods, lack of control, and binge eating (5, 16). Some studies have even found that episodes of stress in these individuals can cause dissociation and lower levels of cognition and self-awareness, which can lead to overeating without actually being aware of it (5,16). So, not only is the dysregulated level of cortisol increasing fat accumulation, but the easily adapted behaviors of binge or overeating compound the potential for weight gain.
The Vicious Cycle of Disrupted Sleep
Another aspect of childhood experiences influencing adult weight gain is disrupted sleep. The correlation between the HPA-axis, lowered sleep quality and duration, and obesity has been well documented (3). Because sleep moderates both the neuroendocrine system (of which the HPA-axis is a part) and glucose metabolism, inadequate sleep has been associated with a higher BMI (6). Further, chronic lack of sleep leads to higher levels of cortisol in the evening, as well as increased appetite late at night, both of which affect sleep quality (6). This leads to a vicious cycle of weight gain, chronic stress, and decreased sleep, all of which feed into each other.
Effects of Inflammation, Gut Health, and Mental Health on Obesity
Experiencing adverse childhood experiences also correlates with increased inflammation overall, as well as an exaggerated inflammatory response to life’s stressors experienced as an adult (7). Obesity is also associated with chronic low-grade inflammation; pro-inflammatory molecules become overabundant in areas of increased adipose tissue (8). This over-abundance can lead to dysregulation of glucose metabolism, which, as discussed above, may already be impaired.
Inflammation is often linked to mental health disorders. Not only do the potential psychological effects of negative experiences in childhood contribute to an increased likelihood of mental health problems, but inflammation itself often accompanies depression, anxiety, and other chronic mood disturbances (9,16).
The gut microbiome is also linked to inflammation, ACEs, and mood disorders. Toxic stress can create an imbalance in “good” bifidobacteria and “bad” staphylococcus aureus bacteria in the gut (11). When imbalanced, the gut microbiome plays a part in the association between the dysregulation of cortisol levels and childhood toxic stress (9,10). This continues into adulthood, so much so that gut bacteria not only differ noticeably in lean vs obese adults but may actually determine whether or not we become obese in the first place (11). Interestingly, prebiotics and probiotics, which promote gut health and bacteria balance, have been found to increase overall health and to decrease the symptoms of anxiety, depression, and overall inflammation (9).
Where to Begin to Reverse the Effects of Toxic Stress?
Given that our experiences in childhood shape so much of our lives, the effects of negative experiences in childhood on our adulthood weight are incredibly interconnected. If you are struggling with your weight and had at least one of the adverse experiences listed above during your childhood, you may be wondering where to begin to fix this complicated issue. A multi-faceted solution is in order: a combination of lifestyle changes, therapy, and stress management can work together to bring real and measurable healing.
Stress Management
Because toxic stress is the underlying root cause of adulthood obesity due to childhood experiences, stress management is a key area of focus for becoming healthier. There are many different ways to manage stress, including grounding and deep breathing techniques, meditation and prayer, journaling, and time spent in nature, to name a few. Introducing one or more of these activities into your weekly or daily routine can help fight against the elevation of stress and cortisol in the body and help curb some of the negative physiological effects mentioned above.
Lifestyle Changes
Poor diet and eating habits, disrupted gut health, and bad sleep hygiene all factor into weight gain and difficulty losing weight. Switching to a diet that emphasizes fruits, vegetables, whole grains, lean meats, fish, beans, nuts, eggs, and other healthy, minimally-processed foods is a great start to creating healthier food habits. Healthy eating is about balance, so limiting sugary, fatty, and comfort foods, staying within your caloric range, and evaluating your eating habits (do you emotionally-, stress-, or over-eat?) can all help you manage your weight (12).
Gut health can be improved in many ways, and a multifaceted approach is the best approach. Stress management, good sleep, and a healthy diet full of plants, lean protein, fiber, and fermented foods all promote a healthy gut (13). Prebiotics and probiotics can bring improvements not only overall physical health but mental health as well.
Good sleep habits, also called sleep hygiene, can improve overall sleep and health. Going to bed at a consistent time, avoiding caffeine, alcohol, and large meals late at night, and exercising regularly can help you wind down more easily each night. Creating a comfortable physical space is another important part of sleep hygiene. Keeping your room dark, quiet, and at a comfortable temperature, and removing electronic devices to avoid extra light or distraction can also help to ensure a good night’s sleep (14).
Resources to Help
Approaching all of these changes at once and trying to determine which your body needs can be daunting. Meeting with a Functional Nutrition & Lifestyle Therapist can help you determine which diet plan may be best for you, help you set up healthier eating habits, and create a plan to help you stick to healthier choices. Medical providers can determine the best treatments, probiotics, and supplements to improv