This is not a book review. This is just me imparting a few things I learned from a book I've just read. The book on the menu today is Always Hungry by David Ludwig, a professor and researcher at both Harvard Medical School and Harvard School of Public Health. The tagline of the book is:

Conquer Cravings, Retrain Your Fat Cells, and Lose Weight

Let's jump in straight away into the lessons this book has taught me.

1 ) Energy Balance Hypothesis VS Hormonal/Metabolic Hypothesis (Guess Which Works)

You've heard the jingle: Calories in, calories out.

What it means is that losing weight should be as simple as eating less and exercising more, no matter what kind of calories you are consuming. That's the energy balance hypothesis in a nutshell and we can safely say that there are a few holes in that theory.

The hormonal or metabolic hypothesis rests on the notion that different types of calories affect us differently, triggering our insulin differently and generally having a different effect on our metabolism. The hormonal/metabolic hypothesis tells us this is something we need to recognize and account for.

In one of his studies, Dr. Ludwig proved just that.

Imagine two milk shakes. One contains corn syrup (a highly processed and fast-acting carbohydrate) and the other uncooked cornstarch (a slow-acting carbohydrate). Their calories are the same, their protein/fats/carbs breakdown is the same, even their sweetness is essentially the same.

Dr. Ludwig brought in twelve men with high body mass index and tested the milkshakes to see what would happen to their blood sugar and insulin, as well as if there would be any differences in the way their brains reacted.

Well, guess what happened next?

First, blood sugar rises more rapidly with the highly processed and fast-acting carbs, but it also drops more rapidly after a few hours, leading to more cravings. Same amount of carbs/fats/proteins, same amount of calories, different results.

2 ) Highly Processed Carbs Hijack Basic Reward Circuitry In The Brain

The other part of the study was focused on conducting brain imaging scans, using a technique called functional magnetic resonance imaging (fMRI). After the participants consumed their shakes, their brains were scanned with the fMRI.

In those that consumed the fast-acting shake a region of the brain called the nucleus accumbens lit up like a laser. It happened with every fast-acting milkshake. Why is this significant? The nucleus accumbens is considered ground zero for reward, craving, and addiction—including alcohol, tobacco, and cocaine abuse.

This suggests that highly processed carbs can hijack the reward circuitry of the brain. This isn't because of their taste (not inherently more tasty), but because of their direct action on the metabolism.

In the words of Dr. Ludwig:

"Hunger is hard enough to fight under any circumstances, but once the nucleus accumbens joins in, it’s all over.”

3 ) Highly Processed Carbs Impair Learning And Focus

Researchers at the University of Wales have discovered, after a study involving seventy-one female undergraduates, that consuming a fast-acting carb-based breakfast leads to drastic impairment of cognitive fuction, when compared to a slow-acting carb-based breakfast.

Verbal memory performance, working memory, selective attention, and executive function were all impacted.

Dr. Ludwig also suggest that we need to look at the diets of our kids and young adults, because these cognitive deficits, if persistent, can lead to a diagnosis of attention-deficit disorder. (!!!)

4 ) A Low-Fat Diet Is Not The Answer

Study after study has found no reduction in heart disease in those who pursued a low-fat diet. Instead, studies are streaming in with evidence of a healthy fat-based diet being exactly what our bodies need to fight against heart disease, diabetes and all sorts of other ailments.

One study in Spain had to terminate early because the groups on the Mediterranean diet were so outperforming those on the low-fat one in reduction of cardiovascular disease, that it became ethically wrong for the participants in the low-fat group to continue with the study.

5 ) Go On A Passeggiata Every Day

A crucial part of being healthy is doing healthy things for the pleasure of doing them. Passeggiata is an Italian word for a type of walk.

"You won’t see anyone wearing a pedometer or spandex during an Italian passeggiata—these walks are purely for pleasure, to get outside and see the neighbors, to reconnect as a family after a long day, and to enjoy the last bit of sunlight. The movement and light that you take in during your passeggiata before nightfall can also recalibrate your body clock. The passeggiata is a moment of joyful movement that helps support healthy digestion and insulin action, while simultaneously relieving stress and helping you sleep better. No matter how fit you are, the passeggiata can reintroduce you to movement in a pleasurable, easy, stress-relieving activity—not a chore to be sweated out and endured."

I hope you liked this post - my new job has me sitting at my desk a lot, often in 16-hour shifts, and I have written, but not posted yet, a ton of these book lesson posts. So many more are coming. Because, what's there to do but write...and take many passeggiatas :-)