Obesity – why we can’t lose (11/4/11)
A Threat to the Nation
Obesity will remain a threat to the American economy and national security for decades to come. With 17% of our GDP spent on health care, we cannot afford treating a nation that will be one third diabetic by 2030. Data argues that every pound Americans add increases national energy costs by $2 billion a year, much of which we pay directly or indirectly to nations that want us dead. And a new study in the New England Journal of Medicine by researchers at the University of Melbourne explains there may be good hormonal reasons for something most know from experience – it’s really hard to lose weight.
The upshot: 1. We cannot allow our child and adolescent obesity epidemic to continue worsening without wrecking our economy and further diminishing our future standing in the world 2. That we need systemic, public health approaches to obesity right now, rather than our Johnny one note approaches of 1001 celebrity diets or buy a discounted membership and live at the gym.
Joseph Proietto and associates in Melbourne wanted to see what happens when people lost more than 10% of body weight. They put fifty volunteers on an unsustainable research diet of 500-550 calories per day, made up of Optifast and vegetables, for ten weeks, before reintroducing them to more normal food.
Thirty four out of 50 lost the required 10% or more of weight, an admirable figure given the draconian diet. In a year they eventually gained about half of it back, also a comparatively good result.
But leptin and ghrelin, thought to act as a sort of yin-yang hormonal effectors of weight, at a year later still remained at levels that signify hunger.
Researchers could not be very surprised. Leptin and ghrelin changes are markedly changed, even wiped out by gastric bypass surgery, which some believe is the main reason the surgery works. Leptin and ghrelin also quickly change with partial sleep deprivation, another reason why so many people are perpetually hungry.
Yet the Melbourne result remains sobering – once people lose weight, their bodies continue to provide potent signals that it wants that weight back – badly.
Born To Fight Starvation
Some implications include :1. The Melbourne study fits an increasingly popular evolutionary model that human bodies are made for intermittent starvation, not the present situation where American producers put out nearly 4000 calories of food per day per person (though even this superabundance is selective – the estimate is that 14.5 million households at least occasionally go hungry in America.) Over millions of years we have evolved to store calories for expectable emergencies, which makes supermarkets with cheap calorically dense foods as attractive to us as blood banks to vampires.
2. Yes, it’s hard to lose weight. We may have to view obesity the way we do osteoarthritis – a chronic condition we can palliate but often not yet overcome. The trick to being healthy is to stay healthy, properly regenerating our bodies each day – and the trick to treating obesity is to avoid it.
3. That we need to start government action, as suggested in the recent obesity issue of the Lancet, regulating children’s food advertising and provisioning. Do we need our kids eating huge amounts of super sugary foods, cheapened by agricultural subsidies, incessantly sold to them from birth onward? Not unless we want to support an even more gargantuan health care system with money we clearly don’t have. Food may be love, but its public costs are skyrocketing.
Along the way, we need to change our view of health in order to make real progress.
Machine or Organism?
Too many people, including physicians, see the body as a machine. Aging means the machinery slowly breaks down before doddering with age. Illness harms the machine more quickly, even terminating it.
This machine view of our body is supremely unhelpful if we are to defuse our obesity epidemic:
1. Weight is clearly changed by many factors beyond diet and exercise, including A. Sleep and rest – especially sleeping less than six hours a day B. Environment (people eat a lot more in a red room than a blue room) C. Social networks – like the studies showing weightier friends make for a weightier you D. Genetics E. Stress – including economic stress like that we have now F. Body clocks – weight going up, along with lipids and glucose, by eating more at night – as in our biggest meal of the day, dinner.
Of course this is far from a comprehensive list of factors that change weight.
2. Your body changes minute to minute, hour to hour, replacing and rebuilding itself continuously. Most of its innards are gone within four weeks; cellular reprocessing research shows that heart, for example, gets mainly replaced in three days.
We don’t just lose and gain weight; we lose and gain ourselves, rebuilding differently every day.
Of course, we don’t “see” most of these changes. We see our hair and our nails grow, but not the new brain cells induced by exercise, nor the complete remaking of the gut within days. Neither do we see viruses generating and mutating by the billions every few hours, nor the enormous effort of our immune system to learn and adapt quickly if we are to survive till tomorrow. Our approach has been to discount this enormous velocity of life – because it’s invisible to us.
But we can understand that biologically we use ourselves up pretty fast – which is why we continuously need new food to survive. And we intuitively understand we’re not the same from day to day, let alone minute to minute – we know that by watching ourselves age.
So what constitutes a more useful public and personal approach to obesity?
The Informative Information Approach
Physics does it; chemistry does it; why not medicine and public health? This is the information age, promulgated in 1948 by Shannon’s now famous information equation. Physicists now write about quantum information theory, not quantum mechanics.
So too with your body. Your body processes information. You process it, remember it or forget it – an amazing form of continuous, mainly unconscious learning that literally keeps you alive. Without it, for example, we would never be able to control infection and cancer.
And such an approach may provide a key to overcoming the obesity epidemic. It allows us to look at the different systems controlling weight – more of the whole picture. Then we can recognize and understand that what we eat, how we eat, what we do with food and our bodies is all part of the information flow that makes us fat or thin.
To control weight and defy obesity we have to acknowledge all that information – and where and how it flows. Yes, the different systems are complex – which means that the cauliflower or the lemon peel diet, even the “right” combination of amphetamines and appetite suppressants, ultimately won’t work for most of us. We have to live with the knowledge that our body is designed for intermittent starvation, and do what it is designed to do – not just what we like at the time, believing we can “fix it” later on by dieting.
A systematic, information approach points us in directions that really work – that weight will be impacted by how we put together food, activity, and rest, and providing proper spaces and places for each; that food and agricultural policy is automatically health policy; that what we do is what we become, and we become something new every morning of our lives, whether or not we see those changes externally on our face or weight scale.
And with change comes opportunities – many – to remake our own health and that of the people around us.
Opportunities that should prove greatly to our advantage.