Posted on 06/11/2026 7:50:01 PM PDT by aimhigh
Researchers at the Monell Chemical Senses Center found that common dietary sugars fructose and glucose, despite having the same amount of calories, communicate with the brain through different gut-brain pathways, a difference that may help shape our food and beverage preferences. In mice, the team identified a dedicated gut-brain signaling pathway through which fructose communicates with the brain and found that it is much less effective than glucose in turning down the activity of hunger-related neurons.
Their findings were published June 10 in Neuron. “This work adds to our growing understanding of how modern diets, especially those high in fructose or high-fructose corn syrup, interact with the neural systems involved in appetite,” said senior author and Monell Member Amber Alhadeff, PhD.
Recording neural activity in mice, researchers observed that fructose triggered a rise in the gut hormone PYY, which then acted through the vagus nerve to modestly inhibit agouti-related protein (AgRP) neurons, key brain cells that help drive hunger. Disrupting this pathway blocked fructose’s effect on those neurons. By contrast, glucose did not rely on this same PYY-Y2 vagus nerve route, researchers said, and caused strong suppression of AgRP neuron activity.
The team found that while both sugars had similar short-term effects on how much mice ate, the animals developed food preferences linked to the level of AgRP inhibition associated with each sugar. The team also looked at high-fructose corn syrup (HFCS), a common food additive that contains a mixture of fructose and glucose. The mice preferred the HFCS, and HFCS more strongly inhibited AgRP neurons than fructose alone. This may help explain why some people find HFCS-containing foods and beverages especially appealing, researchers said.
The findings challenge the long-standing idea that hunger-related AgRP neurons track calorie intake regardless of nutrient source. Instead, this study suggests that these neurons distinguish between sugars and respond to them through different biological pathways. Although fructose and glucose contain the same amount of calories, the animals’ brains did not treat them equally. These new results illustrate the complexity of nutrient sensing: even simple sugars can differently influence the gut, the brain, and our behavior.
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Hell, I’m all for this for medicine:
LSD (lysergic acid diethylamide) is a powerful, man-made psychedelic drug. It alters a person’s thinking, emotions, and sense of time. People who use it often have intense visual hallucinations. It was first made in 1938 from a fungus that grows on grain.
bkmk
bkmk
I thought that was common knowledge, but maybe it is just one of those things I assumed based on logic and an understanding of how the body works.
Regardless I am willing to bet that there are some national and multinational food conglomerates that also have known this for a long time.
maybe I will look it up on OpenEvidence ai at some point
I asked the AI, and it summarized the below studies:
1.
Attenuated Hypothalamic Response to Fructose via a Dedicated Gut-Brain Pathway.
Neuron. 2026. McKnight AD, de Araujo A, Hsu FY, et al.Recent
2.
Dissociable Behavioral, Physiological and Neural Effects of Acute Glucose and Fructose Ingestion: A Pilot Study.
PloS One. 2015. Wölnerhanssen BK, Meyer-Gerspach AC, Schmidt A, et al.
3.
Effect of Glucose and Fructose on Food Intake via Malonyl-CoA Signaling in the Brain.
Biochemical and Biophysical Research Communications. 2009. Lane MD, Cha SH.
4.
Effects of Fructose vs Glucose on Regional Cerebral Blood Flow in Brain Regions Involved With Appetite and Reward Pathways.
The Journal of the American Medical Association. 2013. Page KA, Chan O, Arora J, et al.
5.
Differential Effects of Fructose Versus Glucose on Brain and Appetitive Responses to Food Cues and Decisions for Food Rewards.
Proceedings of the National Academy of Sciences of the United States of America. 2015. Luo S, Monterosso JR, Sarpelleh K, Page KA.
| Sweetener | Fructose % | Glucose % | F:G Ratio | Notes |
|---|---|---|---|---|
| Table sugar (sucrose) | 50 | 50 | 1:1 | Standard reference; disaccharide cleaved to 50/50 |
| High fructose corn syrup (HFCS-55) | ~55 | ~42 | 1.3:1 | Common in beverages; higher fructose load than sugar |
| HFCS-42 | ~42 | ~53 | 0.8:1 | Used in some processed foods; closer to sucrose |
| Honey | ~38 | ~31 | 1.2:1 | Remainder is disaccharides; varies by source |
| Agave nectar | ~90 | ~8 | 11:1 | Extremely fructose-heavy; poor choice for glucose control |
| Maple syrup | ~0.2 | ~67 | 0.003:1 | Mostly glucose + sucrose; minimal fructose |
| Fruit juice concentrate | 30–60 | 20–50 | Varies | Depends on fruit type; apple/pear are fructose-dominant |
| Dextrose (glucose monohydrate) | 0 | 100 | 0:1 | Pure glucose; direct glycemic response |
| Fructose (crystalline) | 100 | 0 | ∞ | Pure fructose; minimal glycemic spike but hepatic load |
| Alulose | N/A | N/A | N/A | Rare monosaccharide; ~90% caloric reduction; GI ~0; minimal glucose impact |
| Stevia | 0 | 0 | N/A | Non-nutritive; no glucose or fructose |
| Monk fruit | 0 | 0 | N/A | Non-nutritive; zero sugar |
| Sorbitol/xylitol | 0 | 0 | N/A | Sugar alcohols; different metabolic pathway |
I've been using a Lakanto blend of Allulose and Monk Fruit. It's pretty good. I bought some Agave nectar a while back thinking it was a good health alternative, but it turned out to be very bad. I'm using it up a little bit at a time rather than tossing it out. I only use sweeteners on morning oats and Greek Yogurt. I'll often sweeten the Greek Yogurt with some lite syrup canned peaches, raspberries, blackberries or blueberries.
“Dissociable Behavioral” — so Karmelo Anthony was ingesting too much fructose? Somebody should tip off his lawyer.
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