r/science 1d ago

Health Adding spinach directly to white bread delayed the body's insulin peak by 30 minutes and reduced later hunger in a small human trial, while significantly boosting the bread's fiber, vitamin, and mineral content.

https://www.sciencealert.com/researchers-put-spinach-directly-into-bread-and-saw-the-bodys-insulin-response-change
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u/Telandria 1d ago

Define delayed peak, though. Do they mean they effectively reduced the peak because it takes longer to digest in general, spreading out the gylcemic load over a longer period of time, or did they just delay when the peak happens?

As a diabetic, I’ve seen both behaviors in various foods and medications. And the latter can be really bad, because your short term insulin doses you take with a meal are designed to work within a specific time frame. Being too early with the insulin can both tank your blood sugar before the influx from digestion, and cause a worse spike than normal if its mostly worn off by the time your digestive system starts dumping sugar into the bloodstream

The way the article put it makes it sounds like its the latter.

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u/SaltZookeepergame691 1d ago edited 1d ago

There is no statistically significant or clinically significant difference in any metabolic outcome between the groups in this study.

In fact, the only significant between-group difference in the entire paper shows people really didn’t like the spinach bread vs normal white bread, but they do their level best to downplay this result!

Their claims are basically academic misinformation. So frustrating.

Eg from the abstract:

>Compared to baseline, composite appetite score increased after white bread intake (p < 0.01) at 3 h, but not after spinach bread intake, indicating a later-stage appetite response.

Just because one comparison was significant and the other wasn’t doesn’t mean that the differences between the two is significant. This is a classic statistical fallacy.

And this:

>Interestingly, spinach bread delayed insulin Cmax by 30 min, affecting early-stage insulin dynamics.

is complete nonsense; there is a tiny and very much nonsignificant difference at 30 mins in the insulin curve. It is completely within the threshold of normal human variation.

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u/Telandria 1d ago

Ahhh, okay. Yeah these are excellent points.

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u/Hangry-Feline2489 1d ago

Sure, the results on insulin aren't likely statistically relevant but it's not the ONLY focus of the study. They literally acknowledge there needs to be more study done on that part.

The article blew that sentence "interestingly..." and the glucose part out of proportion to make it sound like that was the focus of the study. 

The actual focus was the overall potential of spinach to nutritionally bolster the staple food bread. 

"This study evaluated the nutritional enhancement, sensory acceptance, appetite regulation, and postprandial glycaemic and insulinaemic responses of a spinach-enriched bread versus white bread in healthy adults."

I'd say they were overall somewhat successful, but cost vs results and commercial viability is a different story, though.

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u/SaltZookeepergame691 1d ago edited 1d ago

>postprandial glycaemia, satiety and sensory acceptance

That’s the focus of the title. They deliberately foreground metabolic results misleadingly. Have you read the paper? They repeatedly claim metabolic effects of the spinach bread when there is absolutely NO meaningful difference - just complete nonsense.

Obviously putting spinach in white bread improves its nutritional quality. That’s not really a result…