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Striking study reveals how dietary fats enter the brain and cause depression

Striking study reveals how die...
A new study demonstrates how fatty acids can enter the brain and disrupt signaling pathways that lead to depression
A new study demonstrates how fatty acids can enter the brain and disrupt signaling pathways that lead to depression
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A new study demonstrates how fatty acids can enter the brain and disrupt signaling pathways that lead to depression
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A new study demonstrates how fatty acids can enter the brain and disrupt signaling pathways that lead to depression

An intriguing new study, led by scientists from the University of Glasgow, suggests there is a direct causative link between eating a high-fat diet and the development of depression. The new research demonstrates how certain dietary fats can enter the brain, disrupt specific signaling pathways in the hypothalamus, and subsequently induce signs of depression.

Scientists have long observed a strong correlation between obesity and depression and, while it may seem like the two are simply interlinked through obvious psychological associations, some studies are starting to suggest the connection may actually be underpinned by biological mechanisms.

One compelling study from 2018 found that mice given a high-fat diet displayed depressive behaviors until microbiome-altering antibiotics returned their behavior back to normal. This study inferred that high-fat diets may cultivate certain populations of gut bacteria that have the capacity to induce neurochemical changes leading to depression symptoms.

This new study moves away from specifically investigating gut bacteria to examine what neurological mechanisms could be triggered by high-fat diets that lead to the development of depression. After the research initially verified that both dietary and genetically induced obesity led to depression-like behaviors in mouse models, the scientists zoomed in on what was happening in the animal's brains to induce the changes.

The research revealed that the characteristics of depression were being induced in the animals through disruptions in the cAMP/PKA signaling pathway in the hypothalamus. It was further revealed that these disruptions were caused by the accumulation of different dietary fatty acids directly in the hypothalamus. This striking finding is the first time scientists have seen dietary fatty acids move through the bloodstream, accumulate in a specific region of the brain, and then induce depression-like behavioral changes.

"This is the first time anyone has observed the direct effects a high-fat diet can have on the signaling areas of the brain related to depression," says lead author on the study, George Baillie. "This research may begin to explain how and why obesity is linked with depression and how we can potentially better treat patients with these conditions."

For some time scientists have noted obese patients suffering from depression respond poorly to antidepressant treatments compared to lean patients. This study raises an interesting hypothesis, suggesting a potential new generation of antidepressants that can specifically target this neurological mechanism and deliver an effective novel drug to overweight or obese patients suffering major depression.

"We often use fatty food to comfort ourselves as it tastes really good, however in the long term, this is likely to affect one's mood in a negative way," says Baillie. "Of course, if you are feeling low, then to make yourself feel better you might treat yourself to more fatty foods, which then would consolidate negative feelings."

The study also suggests the association between obesity and depression is not entirely bi-directional. A high-fat diet can possibly directly induce the onset of depression symptoms. Observational studies in humans have so far delivered mixed conclusions on whether an unhealthy diet actively causes depression and this new study has only demonstrated this neurological mechanism in animals.

The new research was published in the journal Translational Psychiatry.

Source: University of Glasgow

15 comments
InMice
In Mice!
ProjectPete
Define high fat. What's the sugar intake alongside that?
uday pasricha
Always worried that science is funded to consistently go after only fats & conveniently leave out carbs and sugar. We read that Alzheimer is being referred to as Diabetes 3 & sugar is linked to so many ailments. Then the many reports low carb high fat diets are reversing many lifestyle ailments We know there are so many types of fats, their origin is critical, the type of feed of the animal creates a difference. The target is usually saturated fats. But fats need to be defined & compared with fried fats and with transfats. Fats with carbs is different than fats on their own. The list against carbs and sugar is overwhelming, and we hope that publishers always find out who funded the research. Results on mice linked to dietary tests do not deserve headlines similar to drug trials.
JohanJ
Yes, what kinds of fats did they eat etc. This is clearly the high carb lobby trying to get you to eat what actually makes you sick. Obese people are seldom obese from eating HEALTHY fat but from eating high carb. That raises insulin that signals to the body to store fat. Cutting the carbs is the only way to reverse the process. And then you have to replace the carbs with HEALTHY fats that fuel the brain and make you feel better, not worse. But if you make millions of $ from selling this rubbish advise why would you stop. Keep them sick - that's what pays for the Ferrari!
F. Tuijn
It would be better to find the types of fatty acid doing the damage and reduce these in human nutrition. Or is the intention to support the pharmaceutical industry and not damage the profits of the food industry?
dfmd
Where to start? This study is an example of 21st century phrenology juiced up with Sci-Rap. Nice work guys! It has turned my Cerebrum into a flight risk. Alright, who took my PDE-5 inhibitors? (Funding source hiding behind the Amygdala.)
Douglas Bennett Rogers
I went from 210 to 170 by going gluten free and maintaining caloric content with increased fats. I greatly reduced the swelling in my feet. I needed my gall bladder out after this, probably because of the caloric restriction. I later regained the weight by increasing consumption of mostly egg whites.
Paul.
Complete hog wash, I'm currently on a Ketogenic eating plan, high fat, moderate protein, and low Carbohydrate. I'm not depressed and neither are the hundreds of others on Keto that I know of. In fact, I've lost 80 pounds so far and as I type this I'm wearing the Hawaiin shirt that I last wore 18 years ago when I met my wife.... I'm far from depressed and about 75% of what I eat is healthy fats. The scientists in Glasgow need to rethink their scientific process... they found the answer they wanted to find.... that ain't science.
EZ
It would be nice if there were more details made public by these scientists pursuing certain research goals, ie. who's paying them for their work and why. Unfortunately, we are just the consumers of their efforts. I don't think they want us consumers to know what's going on behind door #3.
Mark Uzick
Junk "science" promoting junk food!