Tomoaki Shirakawa_No.5

Q: How did the anthor address the question?

■Step1 1) Separating food odors from nutritional content The authors fed mother mice a bacon-flavored diet with the same nutritional composition as normal chow. Their offspring showed increased adiposity and insulin resistance when fed a high-fat diet in adulthood. ■Step2 2) Investigating changes in neural responses to food The authors examined dopaminergic reward circuits and hypothalamic AgRP neurons. They found that early exposure to bacon-related odors caused long-lasting changes in neural responses to food. ■Step3 3) Testing whether sensory stimulation alone is sufficient Passive odor exposure or optogenetic stimulation of olfactory neurons alone did not increase obesity susceptibility. However, combining olfactory stimulation with caloric intake increased obesity susceptibility in female mice.

kawaokashinpei3

11 minutes ago

2 min read

Selected journal : Nature Metabolism

Fat sensory cues in early life program central response to food and obesity

https://www.nature.com/articles/s42255-025-01405-8

What is the main question of the paper?

Can exposure to food odors during early life affect susceptibility to obesity later in life, independently of nutritional content?

How did the anthor address the question?

■Step1

1) Separating food odors from nutritional content

The authors fed mother mice a bacon-flavored diet with the same nutritional composition as normal chow. Their offspring showed increased adiposity and insulin resistance when fed a high-fat diet in adulthood.

■Step2

2) Investigating changes in neural responses to food

The authors examined dopaminergic reward circuits and hypothalamic AgRP neurons. They found that early exposure to bacon-related odors caused long-lasting changes in neural responses to food.

■Step3

3) Testing whether sensory stimulation alone is sufficient

Passive odor exposure or optogenetic stimulation of olfactory neurons alone did not increase obesity susceptibility. However, combining olfactory stimulation with caloric intake increased obesity susceptibility in female mice.

What is the strength of the paper?

I think the most interesting aspect of this paper is how the authors separated the effects of food odors from nutritional content. They also tested whether exposure to odors alone was sufficient to increase obesity susceptibility and found that pairing sensory stimulation with caloric intake was important. I found it particularly interesting how they refined their initial hypothesis through a series of well-designed experiments, gradually identifying the key factors involved.

Comment

In response to the long-held belief that “a mother’s high-fat diet increases a child’s risk of obesity,” they are reexamining the question, “Is nutritional composition really the cause?” and developing a model that can manipulate only sensory information. I think their greatest contribution lies in experimentally isolating factors that had previously been overlooked and introducing a new concept into obesity research.

Comment by Yuki Nakamura