Health & Wellbeing

New discovery may make losing weight and keeping it off much easier

New discovery may make losing weight and keeping it off much easier
A change in the brain's neural pathways while dieting facilitates rebound weight gain
A change in the brain's neural pathways while dieting facilitates rebound weight gain
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A change in the brain's neural pathways while dieting facilitates rebound weight gain
A change in the brain's neural pathways while dieting facilitates rebound weight gain

Anyone who has achieved it knows that maintaining weight loss long-term is an uphill battle. The hormonal, metabolic and neural factors that regulate body weight means it can be more a matter of biology than willpower. At the same time, the global weight loss industry is valued at US$224 billion and is set to grow to $405 billion by 2030.

One of the most frustrating aspects for many is the yo-yo effect of calorie restriction, that sees dieters regain half of their lost pounds within two years, and around 80% after five. This is often seen as a personal failure and can have long-lasting physical, emotional and psychological impacts.

But it may not be all doom and gloom. Researchers from the Max Planck Institute for Metabolism Research (MPIMR) and Harvard Medical School have identified a significant change in neural pathways in the brain that occurs when dieting, with much stronger signals traveling to the nerves that mediate feelings of hunger. Inhibiting these signals may help scientists develop treatments that better assist people in maintaining their weight.

“People have looked mainly at the short-term effects after dieting,” said Henning Fenselau, a researcher at MPIMR, who led the study. “We wanted to see what changes in the brain in the long term.”

To do so, the researchers put mice on a diet and monitored brain circuitry, focusing in on the Agouti-Related Peptide (AgRP) neurons in the hypothalamus, known to control feelings of hunger. Previous studies have shown how stimulating these neurons leads to acutely elevated food consumption. They found that the neuronal pathways to the AgRP neurons amplified when the animals were on the diet and remained at those amplified levels, resulting in extreme hunger signals that led to greater food intake and quicker weight gain.

“This work increases understanding of how neural wiring diagrams control hunger,” said co-author Bradford Lowell from Harvard Medical School. “We had previously uncovered a key set of upstream neurons that physically synapse onto and excite AgRP hunger neurons. In our present study, we find that the physical neurotransmitter connection between these two neurons, in a process called synaptic plasticity, greatly increases with dieting and weight loss, and this leads to long-lasting excessive hunger.”

When the researchers inhibited the connection between those neurons, AgRP activity decreased and the animals had a more regulated response to food intake. Not surprisingly, this led to significantly less weight gain.

“This could give us the opportunity to diminish the yo-yo effect,” said Fenselau. “In the long term, our goal is to find therapies for humans that could help maintaining body weight loss after dieting. To achieve this, we continue to explore how we could block the mechanisms that mediate the strengthening of the neural pathways in humans as well.”

The study was published in Cell Metabolism.

Source: Max Planck Institute for Metabolism Research

That’s great news. However, I feel strongly that much better education of the general public and healthcare professionals as to what foods actually make you fat would be more important and potentially be a much greater factor in reducing obesity globally. I still regularly see advertisements and information, published by organisations that really should know better that fail to differentiate between calories contained within carbohydrates, and those contained within fats, the latter being almost completely irrelevant in terms of obesity. How long is it going to take for our respective governments to wake up to the cynical marketing ploys used by the food industry for the last 30 years to perpetuate the myth that ‘eating fat makes you fat’, all the while peddling their obscenely high-profit margin, food stuffs, rammed with highly processed carbohydrate (not to mention salt) before some sort of serious action is be taken? Personally, I’d like to see an immediate ban on advertising of any foodstuff that contains more than 40% carbohydrate, if not an outright ban on the worst offenders, for example, sugary fizzy drinks.
We know there are neurological changes mitigated by neurotransmiitter releases. But how do we block those neurotransmitters without screwing up the rest of the system. You can educated people who are normal diet, but you cannot educate in therapies that block the up-regulated neurotransmitters declaring ongoing starvation! A great article if there was a therapy outcome in the works!
Michel Driessen
I agree with Sri Aurobindo: technology is merely creating protheses for people cut off from their natural abilities.
I also agree that for example scuba diving is great. But apnoea is much better. It only takes a lot more training.

Obesity has never been such a big problem as now, because of toxins purposefully mixed with our foods. First of all check you psychology and alter your eating habits and diet to something more sound.
Right on, especially those sugary fizzy drinks!
Hunger and satiety are more controlled by the phytonutrient supply to our body and our microbiome than some associated (not causal) neurotransmitter fluctuation. The real problem is our factory farmed and chemical lab foods. Reintroduce wild foods and heirloom varieties of cultivated foods and our weight falls, stays low and no yo-yo effect on-going. Diet then go back to a rubbish diet and the weight is piled back on. Duh.
Sometimes I get the feeling the "food" industry, and the "diet" industry are in bed with each other.
The food industry over processes food, people eat it, get fat, then the diet industry pushes a weight
loss idea. Once people lose the weight, the food industry kicks back in.
martinwinlow: bullseye!
I have been on an intermittent fasting diet for going on 6 years,and find it easy to stick to. I am ~ 182 lbs,and used to be 201. If you are living with someone,mealtimes might be a problem,as you would likely be skipping breakfast,and eating 2 meals a day.
Jay Gatto
Tax sugar, and simple carbs, as we do energy. Make into ethanol, or translate into mechanical motion more directly. And if neurotransmitters can be safely regulated, why not. Good quality fat is your friend.