Nav: Home

Mice study implicates fat as obesity cause

July 13, 2018

What we eat plays a big role in our ability to regulate our body weight. Over time, however, different ideas have emerged about the most important dietary factors that cause us to put on weight.

During the 1980s and 1990s, it was widely accepted that the most important factor in weight gain is the fat content of our diets. However, in the new millennium it was suggested that this focus on fat was misplaced, and that, in fact, the main factor driving obesity was our carbohydrate intake - notably, our intake of refined carbohydrates like sugars.

Several hugely popular books were published in this period suggesting that eating fat might actually protect us from obesity.

Most recently, however, attention has turned to protein, with the hypothesis that people eat food mostly to obtain protein rather than energy.

According to this idea, when the protein content of our diet falls, we eat more food to meet our target protein intake. That makes us consume too many calories and we get fat. Since our food consists of fat, protein and carbohydrates - and at different times all three have been implicated in making us obese - it is difficult to know what to eat to stay slim.

Part of the problem is that it is very difficult to do human studies that control food intake long enough to determine what dietary factors cause weight gain. Studies on animals similar to us, however, can suggest possible answers.

Now scientists at the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences in Beijing and the University of Aberdeen in Scotland have performed the largest study of its kind to resolve what components of the diet cause mice to put on body fat. The study was published today in the journal Cell Metabolism.

The study included 30 different diets that varied in their fat, carbohydrate (sugar) and protein contents. Mice of five different strains were fed these diets for 3 months, which is equivalent to 9 years in humans.

In total, over 100,000 measurements were made of the mice's body weight changes and their body fat was measured using a micro MRI machine. The result of this enormous study was unequivocal - the only thing that made the mice get fat was eating more fat in their diets. Carbohydrates, including up to 30% of calories coming from sugar, had no effect.

Combining sugar with fat had no more impact than fat alone. There was no evidence that low protein (down to 5% of the total calories) stimulated greater intake, suggesting there is no protein target. The researchers believe that dietary fat caused weight gain because fat in the diet uniquely stimulated the reward centers in the brain, thus causing greater intake of calories.

Professor John Speakman, who led the study, said "A clear limitation of this study is that it is based on mice rather than humans. However, mice have lots of similarities to humans in their physiology and metabolism, and we are never going to do studies where the diets of humans are controlled in the same way for such long periods. So the evidence it provides is a good clue to what the effects of different diets are likely to be in humans."
-end-


Chinese Academy of Sciences Headquarters

Related Weight Gain Articles:

Keeping young women's weight gain to less than 800g/year could help prevent progression from healthy weight to overweight and obesity
New research presented at this year's European Congress on Obesity (ECO) in Porto, Portugal (May 17-20) shows that rates of weight gain are established by the time women are 18-23 years old.
Parkinson: Weight gain after deep brain stimulation
It was already known that people affected by Parkinson's disease, when subjected to deep brain stimulation, gained weight, but it was less clear why that was so.
Even 'healthy' weight gain raises pregnancy diabetes risk
Mothers who gain weight in the years leading up to pregnancy have an increased risk of gestational diabetes.
Healthy weight gain in infants
With nearly 10 percent of infants considered 'high weight for length,' University of Delaware researcher Jillian Trabulsi wants to help babies achieve a healthy weight starting with their first months of life.
Avoiding medications that promote weight gain when managing obesity
While diet, exercise and behavior modification are essential components of obesity management, a successful long-term weight loss strategy should also include avoiding or minimizing medication-related weight gain, according to a new report from Weill Cornell Medicine.
Children gain more weight when parents see them as 'overweight'
Children whose parents considered them to be 'overweight' tended to gain more weight over the following decade compared with children whose parents thought they were a 'normal' weight, according to analyses of data from two nationally representative studies.
Does good-tasting food cause weight gain?
Does eating good-tasting food make you gain weight? Despite the common perception that good-tasting food is unhealthy and causes obesity, new research from the Monell Center using a mouse model suggests that desirable taste in and of itself does not lead to weight gain.
Yo-yo dieting might cause extra weight gain
Repeated dieting may lead to weight gain because the brain interprets the diets as short famines and urges the person to store more fat for future shortages, new research by the universities of Exeter and Bristol suggests.
Adult weight gain could increase cancer risk
Substantial weight gain over many years increases the risk of obesity-related cancers in men by 50 percent and in women by almost 20 percent, according to new research presented at the National Cancer Research Institute's Cancer Conference in Liverpool.
Metformin associated with decreasing weight gain in kids with autism
The diabetes medication metformin hydrochloride was associated with decreased weight gain in a small clinical trial of children and adolescents with autism spectrum disorder who were taking atypical antipsychotics to treat symptoms of irritability and agitation, according to an article published online by JAMA Psychiatry.

Related Weight Gain Reading:

The Plant Paradox: The Hidden Dangers in "Healthy" Foods That Cause Disease and Weight Gain
by Dr. Steven R Gundry M.D. (Author)

Weight Gain Smoothies: Invigorating High Calorie Shakes
by Danny Gansneder (Author)

How to Gain Weight: From Ectomorph to Mesomorph
by Khail Kapp (Author)

How to Gain Weight: The Hardgainer’s Scientific System to Force your Skinny Body to Grow into a Bigger, Stronger and more Muscular Version of Yourself

Happy Gut: The Cleansing Program to Help You Lose Weight, Gain Energy, and Eliminate Pain
by William Morrow

How To Gain Weight Fast: A Womens Guide: Gain 1 Stone in 8 Weeks

Rapid Weight Gain Smoothies: Strength Training Bodybuilding High Protein Shakes for Fast Muscle Mass Building (Health & Fitness Book 1)

How to Gain Weight Fast for Women

The Voracious Little Mermaid: A Feeder/Weight Gain/Dark Fantasy Book. Granted a wish to go above, Ari discovers two loves: Food and a handsome stranger. Will both be used to punish her?

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Circular
We're told if the economy is growing, and if we keep producing, that's a good thing. But at what cost? This hour, TED speakers explore circular systems that regenerate and re-use what we already have. Guests include economist Kate Raworth, environmental activist Tristram Stuart, landscape architect Kate Orff, entrepreneur David Katz, and graphic designer Jessi Arrington.
Now Playing: Science for the People

#504 The Art of Logic
How can mathematics help us have better arguments? This week we spend the hour with "The Art of Logic in an Illogical World" author, mathematician Eugenia Cheng, as she makes her case that the logic of mathematics can combine with emotional resonance to allow us to have better debates and arguments. Along the way we learn a lot about rigorous logic using arguments you're probably having every day, while also learning a lot about our own underlying beliefs and assumptions.