For years, ADHD experts have recognized the link between untreated ADHD and obesity. As for weight-control experts and gastric-bypass surgeons? Most missed the memo. Is it territorial jealousy? Willful ignorance? “ADHD Denial”?
Let’s be charitable. Consider it one more casualty of our highly specialized medical system. One that too often overlooks undiagnosed ADHD’s contributions to many physical issues.
At the end of this post, I’ll link to another sharing the results of a large study finding ADHD as a risk factor in most chronic conditions, including these:
- Alcohol-related liver disease
- Sleep disorders
- Chronic obstructive pulmonary disease (COPD)
- Fatty liver disease
In short, research increasingly points to a strong correlation between ADHD and obesity.
How strong a correlation? Someone with ADHD is four times more likely to become obese than is someone without ADHD. Brain chemistry, poor impulse control, and erratic sleeping habits all conspire to encourage unhealthy eating — and to make weight loss feel or be impossible.
The implications are clear: Treating ADHD early means many people could avoid these disabling illnesses and conditions. Even treating ADHD later, after these conditions have set in, could still help reverse or at least slow disease progression while also treating ADHD symptoms, perhaps for the first time.
Make no mistake: Anyone considering drastic weight-loss or sleep-apnea surgeries should first consider screening for ADHD. Don’t expect that your weight-loss specialist or surgeon or sleep specialist will know how to recognize ADHD. Also know about the psychological misattributions to eating disorders — such as trauma, anxiety —with ADHD not even on the radar.
This Post’s Takeaway Points
- Stimulant medication can reduce vulnerability to obesity for people with ADHD
- Eating can be “stimulating” (see #1 for a more reliable, regulated form of stimulation)
- Chronic disorganization common to untreated ADHD means no food at home, poor inclination to cook, plan meals, etc….so eat fast food or whatever’s handy (chips, donuts, etc.).
- Forgetting when you last ate!
- Poor read of the signals (e.g. Body says, “we’re full now” but you don’t hear it or can’t act upon it…you can’t “put on the brakes”).
- Poor sleep contributes, too.
- Disorganization and lack of follow-through in getting regular exercise.
Below you’ll find:
- Early research on ADHD and obesity
- Words from veteran ADHD expert who early on spotted the ADHD-obesity connection
- More recent research
Digesting the Early Findings: ADHD and Obesity
Toronto-based psychologist John Fleming, Ph.D is among the first researchers to link ADHD and weight gain.
In 2009, physician Lance Levy, MD joined Fleming in attempting to answer this question: Will medically treating severely obese subjects with newly diagnosed ADHD result in sustained weight loss?
Here are the summaries for their two early studies:
- The 2005 study evaluated for ADHD 76 women referred to a medical specialist for the non-surgical treatment of obesity. Of the 76 women, 26.7 percent reported significant symptoms of ADHD in both childhood and adulthood
- The 2009 study found that among study students who had been unable to lose weight by other means, 33 percent were found to have ADHD. After 466 days of stimulant-medication treatment, subjects lost 13 percent of their original weight.
Now let’s examine the details for each study.
2005: How Many Obese Female Study Subjects had ADHD?
Past and current symptoms of Attention Deficit Hyperactivity Disorder (ADHD) were assessed in a clinical sample of severely obese females.
Core symptoms of ADHD were examined in 75 consecutive, severely obese (BMI > or = 35) women referred to a medical specialist for the non-surgical treatment of obesity.
Subjects completed both a retrospective report of childhood symptoms of ADHD (Wender Utah Scale) and two standardized adult ADHD symptom scales.
- The frequency of clinically suggestive elevations in ADHD scores was substantially and significantly higher than the normative samples in 9 out of 11 symptom subscales.
- Inattentive symptoms, but not hyperactive symptoms of ADHD, were frequently reported.
Overall, 26.7% of the sample reported significant symptoms of ADHD in both childhood and adulthood.
This preliminary study suggests that severely obese women report significant symptomatology related to both childhood and adult ADHD.
2009: Will ADHD Treatment Help Obesity?
The first study (2009) identified subjects who had a history of difficulty with weight-loss and who likely had ADHD. The hypothesis? Untreated ADHD was proving an impediment to weight loss.
(For reference, refractory means “hard or impossible to manage” and comorbid means co-existing.)
To determine whether attention deficit hyperactivity disorder (ADHD) pharmacological treatment of severely obese subjects with newly diagnosed ADHD would result in sustained weight loss.
Longitudinal clinical intervention study of the effects of ADHD medication on weight change over 466 days.
78 subjects (6 male, 72 female, mean age 41.3 years, BMI 42.7 kg m(-2)) out of 242 consecutively referred severely obese, weight loss refractory individuals were diagnosed as having ADHD. Sixty-five subjects received treatment and 13 remained as controls.
- Standard screening tests identified subjects likely to have ADHD. A diagnosis was made in 78 subjects by semi-structured clinical interview.
- ADHD subjects were screened for comorbid conditions. That would include binge eating disorder, mood disorder, sleep apnea, chronic pain, and gastroesophageal reflux disease.
- Satisfactory resolution of symptoms of comorbid conditions was achieved prior to the introduction of pharmacotherapy for ADHD.
- Subjects not accepting, tolerating or remaining on ADHD medication served as controls.
- Weight was measured at sequential clinic visits after initiation of pharmacotherapy.
Comorbid [or, co-existing] conditions were found to be highly prevalent :
- Sleep apnea 56.4%
- Binge eating disorder 65.4%
- Mood disorder 88.4%.
After an average of 466 days (s.d.=260) of continuous ADHD pharmacotherapy, weight change in treated subjects was -12.36% of initial weight and in controls +2.78%, P<0.001.
Weight loss in treated subjects was 15.05 kg (10.35%) and weight gain 3.26 kg (7.03%) in controls, P<0.001.
ADHD is a highly prevalent condition in the severely obese population. Treatment of ADHD is associated with significant long-term weight loss in individuals with a lengthy history of weight loss failure.
- This result is likely due to the positive effects of treatment on self-directedness, persistence and novelty-seeking behaviors.
- ADHD should be considered as a primary cause of weight loss failure in the obese.
- Individuals seeking medical or surgical weight loss should undergo evaluation for ADHD and treated appropriately before intervention.
- This may improve the outcome for medically managed patients and avoid complications in surgical subjects because of poor compliance with diet and supplement requirements.
Early Writings: ADHD and Eating Patterns
I first read about this topic in 2002, in a book chapter called “Disordered Eating and ADHD.” Fleming and Levy contributed the chapters to the groundbreaking Gender Issues and ADHD: Research, Diagnosis, and Treatment, edited by Patricia Quinn, M.D. and Kathleen Nadeau, Ph.D. 2002.
Psychologist Kathleen Nadeau and physician Patricia Quinn teamed up originally to address the long-overlooked needs of women and girls with ADHD. They founded The National Center for Girls and Women with ADHD [update: closed in 2013].
In the process —through their many books, lectures, and other efforts — this pioneering pair expanded our knowledge in all aspects of ADHD. Across genders and the lifespan. [See a recent post about their new book, Understanding Girls with ADHD: “A Must-Read about Girls with ADHD”.]
Therefore, it’s unsurprising that Quinn and Nadeau stood on the vanguard of creating awareness on this ADHD-obesity issue.
Consider this excerpt from an early article written by Nadeau, entitled “Diet and Weight Management Strategies for Adults with ADD (ADHD).”
The ADHD/disordered-eating connection is not difficult to understand.
Healthy dietary regulation requires organization and planning— two areas of cognitive functioning that are typically difficult for those with ADHD.
Good eating habits also require self-awareness – awareness of when one is hungry, awareness of when one is full.
Many individuals with (ADHD) report that they skip meals because they were busy and distracted; these same individuals often report that later their hunger becomes so intense that they swing in the opposite direction, overeating well beyond the point of reasonable intake because they don’t know when to stop until they feel “stuffed.”
Individuals eat for many reasons besides hunger – including boredom, self-stimulation, anger, sadness, reward, simple food availability, and stress relief. It is easy to understand how consistent self-regulation, which is a well-documented difficulty for those with ADD (ADHD), can lead to patterns of chronic over-eating.
More Recent Research: ADHD and Obesity
More recently, the literature is mounting on the relationship between ADHD and eating behaviors.
Consider three more recent papers, starting with the most recent.
2021: Half of the children with ADHD and obesity studied reach normal weight with stimulants
Lead researcher Jovanna Dahlgren, MD, is a pediatrics professor at Sweden’s University of Gothenberg. Her research covers a range of topics; she is not an ADHD specialist. Perhaps her cross-disciplinary knowledge aided her ability to make the connections here.
Aim: Treatment of childhood obesity is often insufficient and may be aggravated by high co-occurrence of attention-deficit/hyperactivity disorder (ADHD). We aimed to investigate whether children with overweight or obesity normalised in weight when receiving stimulant treatment for ADHD.
Methods: Growth data of 118 children were obtained from medical records at outpatient paediatric and children’s psychiatric services in the Gothenburg area, Sweden. The children were diagnosed with ADHD and were between 6 and 17 years at the start of stimulant treatment. The pre-treatment data act as an internal control where every child is their own control.
Results: At the start of treatment, 74 children had normal weight and 44 had either overweight or obesity. During the year with stimulants, the mean (SD) body mass index (BMI) in standard deviation score (SDS) decreased significantly: -0.72 (0.66) compared with 0.17 (0.43) during the year before treatment (p < 0.01). After one year with treatment, 43% of those with overweight or obesity had reached normal weight.
Conclusions: Stimulant treatment for ADHD yields significant weight loss. In children with overweight or obesity and ADHD, this is an important finding showing additional benefit in terms of weight management.
2016: Attention-Deficit Disorder and Obesity
Here are some highlights from Attention-Deficit Disorder and Obesity: Update 2016, by Samuele Cortese and Luca Tessari.
- We retained a total of 41 studies, providing information on the prevalence of obesity in individuals with ADHD, focusing on the rates of ADHD in individuals with obesity, or reporting data useful to gain insight into possible mechanisms underlying the putative association between ADHD and obesity.
- Overall, over the past 4 years, an increasing number of studies have assessed the prevalence of obesity in individuals with ADHD or the rates of ADHD in patients with obesity.
- Although findings are mixed across individual studies, meta-analytic evidence shows a significant association between ADHD and obesity, regardless of possible confounding factors such as psychiatric comorbidities.
- An increasing number of studies have also addressed possible mechanisms underlying the link between ADHD and obesity, highlighting the role, among others, of abnormal eating patterns, sedentary lifestyle, and possible common genetic alterations. Importantly, recent longitudinal studies support a causal role of ADHD in contributing to weight gain.
- The next generation of studies in the field should explore if and to which extent the treatment of comorbid ADHD in individuals with obesity may lead to long-term weight loss, ultimately improving their overall well-being and quality of life.
2015: Association between ADHD and Obesity: A Systematic Review and Meta-Analysis
Also from a team headed by Samuele Cortese: Association between ADHD and Obesity: A Systematic Review and Meta-Analysis.
- Forty-two studies that included a total of 728,136 individuals (48,161 ADHD subjects; 679,975 comparison subjects) were retained.
- Researchers found a significant association between obesity and ADHD for both children (odds ratio=1.20, 95% CI=1.05-1.37) and adults (odds ratio=1.55, 95% CI=1.32-1.81).
- The pooled prevalence of obesity was 70% higher in adults with ADHD (28.2%, 95% CI=22.8-34.4) compared with those without ADHD (16.4%, 95% CI=13.4-19.9), and by about 40% in children with ADHD (10.3%, 95% CI=7.9-13.3) compared with those without ADHD (7.4%, 95% CI=5.4-10.1).
- The significant association between ADHD and obesity remained when limited to studies
1) reporting odds ratios adjusted for possible confounding factors;
2) diagnosing ADHD by direct interview;
and 3) using directly measured height and weight.
- Gender, study setting, study country, and study quality did not moderate the association between obesity and ADHD.
- ADHD was also significantly associated with overweight.
- Individuals medicated for ADHD were not at higher risk of obesity.
Links to Related Reading:
Dr. Fleming’s website includes informative articles and video interviews, including articles on these topics:
- Weight Management with ADD: Understanding the Problem and Finding ADD-Friendly Solutions
- ADHD and Disordered Eating
- Symptoms of attention deficit hyperactivity disorder in severely obese women
ADHD & Nicotine: Remember a few decades ago when millions more Americans smoked cigarettes? Remember when smokers complained of gaining weight every time they tried to quit? Nicotine is a fairly effective (if highly problematic) stimulant. I wrote about this topic here: ADHD & Nicotine: Historical Ads.
Dr. Levy wrote this book: Understanding Obesity: The Five Medical Causes (Your Personal Health)
How About You?
Do you suspect that ADHD has affected your or your loved one’s ability to maintain a healthy weight?
And remember: Some people with ADHD might be chronically underweight for reasons similar to those who are overweight. Consider lack of planning, not paying attention to internal phenomenon, and so forth.
This post originally appeared 4/27/09. Updated 8/1/21
I welcome your comments.