The Physiology of Weight Loss
In the context of working extensively with anti-aging, I have to address often how longevity and health span cannot be achieved without a healthy weight. Obesity increases mortality, it’s a fact (cancer, hypertension, Type 2 diabetes, NAFLD, cardio vascular diseases etc). Obesity also increases the risk of dying when the following occurs: stroke, hyperlipidemia, sleep apnea, CHD and more. Obesity is an epidemic in the US in particular. It’s a disease of excess. Obesity is treatable and preventable. However, much stigma and misinformation cloud most people's vision.
I hope this is not too long as it only scratches the surface of weight loss. If you have questions you can always reach out. I don’t design custom protocols or diets or training plans. I prefer to explain the principles & mechanisms and design customized plans with my clients. Everyone is unique.
What is a Healthy Weight?
A healthy weight comes with a BMI less than 25 (weight in kg divided by the square off the height in meters). I know some will argue that BMI is not a good measure of obesity and I disagree because overall we see a correlation (with of course some exceptions). If you disagree with your own BMI (!) I suggest you measure body fat % and assess your weight that way. You can also measure your waist circumference and see if you are within healthy limits (midline adipose is an indicator of visceral fat and heart disease risk). From 25 kg/m2 to 30 one is over weight and above 30 one is obese.
Trying to lose weight without a science-based plan is a physiological tug-of-war: weight loss via reduced-calorie intake (and increased exercise) triggers the process of metabolic adaptation in the brain and body. What happens too often is that patients try “on their own” based on the notion that if they eat less and exercise more they will trim down. The media is always replete with “tips and tricks”. The methods and plans are often based in popular culture or just propagated by health gurus on social media. This is not science or tradition. In my experience this is akin to banging ones head on the wall expecting to become smarter.
Losing weight with the proper understanding of science and letting go of common beliefs is possible. It requires proper diagnosis, metabolic profiling, accurate metrics and yes, great discipline, clarity and honesty. Sleep quality and stress are often overlooked as integral parts of a weight loss plan. There are also supplements that can support an increased metabolism (increasing AMPK for instance) but there are no magic teas (as I’m often asked). It takes determination, focus and time.
And I can hear it already! “But Dr Arno you are so skinny, it’s so easy for you to say”. Well first, I’m not skinny (BMI of 22), skinny would be underweight which I don’t want to be. And when I had my second child it looked like I had accumulated sympathetic pregnancy weight and I wasn’t running so I ended up with a BMI over 30 (Obese, I didn’t “look” obese but the truth is that I was obese and also like most, in denial) and 40 pounds to lose. I lost the 40 pounds by exercising again and monitoring my diet. This was over 17 years ago and I never regained the weight again. I know “weight-loss”. I’ve done it myself. If I had kept that weight I would be at 26% risk of developing hypertension, doubling my odds of ED, increasing NAFLD risk by 42%, costing society $3500 exgtra per year and losing 2.4 years of life. If I can do it. You can too. Let’s look at some little know aspects of weight loss.
Metabolic & Hormonal Responses Affect Ability to Maintain Weight Loss
Weight loss due to calorie restriction may cause the body to react by slowing metabolism and altering appetite-regulating hormones in a process called metabolic adaptation, making long-term weight management difficult.
Which Hormones Are Affected by Metabolic Adaptation?
After weight loss via reduced-calorie intake, metabolic adaptation may result in increased signals for energy intake (increase in the hunger hormone [ie, ghrelin] and decrease in satiety hormones [eg, GLP-1, PYY, CCK, amylin]).
For instance native GLP-1 affects appetite in 2 different ways, by acting as a hormone and a neurotransmitter. It also acts on multiple regions of the brain. As a hormone it is secreted by intestinal cells in response to meals, it travels in blood stream and enters the brain. As a neurotransmitter GLP-1 containing neurons project to multiple brain regions involved in appetite regulation and food reward.
The Brain Plays a Critical Role in Appetite Regulation
For people with obesity trying to lose weight and maintain it, hunger that drives increased eating is a major challenge. After weight loss, metabolic adaptation leads to decreases in resting metabolic rate and lower energy expenditure. The majority of energy expenditure comes from resting metabolic rate. When people with obesity try to lose weight, metabolic adaptation will counteract their weight-loss efforts. Metabolic adaptations must be continuously offset through long-term weight management.
Obesity is a Relapsing Disease
90% of people with obesity are unable to keep weight off long term. A timely and effective weight-management plan can prevent obesity from recurring. Long-term weight loss is defined as losing at least 10% of initial body weight and maintaining the loss for at least 1 year. Weight loss triggers multiple processes that defend baseline body weight and make it very difficult to maintain weight loss. These mechanisms contributing to weight regain persist for at least 1 year. A review of 14 long-term studies showed that people with obesity regained weight after weight loss achieved by dieting.
Weight regain can be caused by multiple factors. I’m here to identify the factors involved and to provide support & communication with patients about sustaining weight loss in the long term. There are pathophysiologic adaptations that promote weight regain and we need to recognize normal weight fluctuations, work with an expert. There is always excess eating during holiday seasons and we need to compensate for the occasional overindulgences. There are multiple approaches to mitigating weight regain
Only 55% of people with obesity receive a formal diagnosis, and even fewer receive long-term obesity care. The health care system fails its users by skirting over the issue at each check up or visit. True that cancer and CVD are much more lucrative for them but also PCPs aren't trained to deal with obesity. They will just say "you should lose some weight"... I'm not that kind of PCP!
- Medical history
- Physical examination
- Clinical labs
- Review of systems, emphasizing obesity-related complications
- Obesity history
- Chart weight vs age
- Lifestyle patterns and preferences
- Previous interventions
- Confirm elevated BMI represents excess adiposity
- Measure waist circumference to evaluate cardiometabolic disease risk
- Normal weight: BMI <25 kg/m2*
- Overweight: BMI 25 kg/m2–29.9 kg/m2
- Obesity: BMI ≥30 kg/m2
- Evaluate checklist of obesity-related complications (I can calculate your risk of developing comorbidities i you give me your weight, height and birth sex)
Recommended Methods for Weight Loss
- 5 to 10% initial goal with 6 months is reasonable. Achieving the goals of approximately 5% to 10% of initial weight with a comprehensive lifestyle intervention should be considered successful weight reduction that leads to decreased risk for development or amelioration of obesity-related medical conditions (i.e., hypertension, hypercholesterolemia, elevated blood glucose) and CVD risk factors for many patients. Some patients will require additional weight loss to achieve targeted health outcome goals.
- Weight loss requires creating an energy deficiency through caloric restriction, physical activity, or both.
- While weight loss treatment is ongoing, manage risk factors such as hypertension, dyslipidemia and other obesity-related conditions.
- After 6 months, most patients will equilibrate (caloric intake balancing energy expenditure) and will require adjustment of energy balance if they are to lose additional weight.
- For adults with a BMI ≥40 (or BMI ≥35 with obesity-related comorbid conditions) who are motivated to lose weight and who have not responded to behavioral treatment with sufficient weight loss to achieve targeted health outcome goals: bariatric surgery may be an appropriate option to improve health and I’m happy to refer when appropriate. FYI liposuction is not recommended.
Weight Loss & TCM
In Chinese medicine we view excess of adipose tissue as Damp, which is considered to be a pathogen (it will make you sick, actually dampness is a sickness pattern). Depending on your constitution the goal of acupuncture and herbs is to reduce damp. Of course again, there is no magic bullet here. I can often see Qi Stagnation in connection with Dampness also with Liver attacking the Spleen. And Damp often progresses to Damp Heat. As we age the Damp Pattern starts to merge with aging patterns such aa Kidney Yang Deficiency, Heart Qi Deficiency.
No one loses weight from acupuncture only (I’m asked that question routinely). Once someone was always requesting “the metabolic point” (ST36) and I was confused as to where they learned that one point on the leg would increase their base metabolism to create a energy deficit! However, regular acupuncture visits are a good way to check in on your weight loss journey and I’m here to hold you accountable and be your friend (not the weight police, although that would be very French of me). I work as a team with my weight loss patients and I demand a commitment on their part to do what is required. Then it works very well. Win win.
This was a long newsletter this week (there was no newsletter last week, now you know why). I feel it’s not even complete but there is a lot to talk about when it comes to treating the obesity epidemic. I understand the word obese might be discomforting and might bring feelings of shame and that’s ok. Not here to judge, just here to support and help you get to your better healthy self!
Be safe and be be well!
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