Carbs and Bi-Phasic Hunger ~ why is that cereal making me so damn hungry!?

I love a good bowl of sugary cereal, however I hate being hungry 3hrs later. In theory, why is eating food and in particular carb-rich foods making us more hungry? Here are a few reasons why:

1- Carbs are quickly used.

They did a study of a glucose load (sugar) and a fat load (in this case cream). They then traced how quickly blood sugar levels and blood triglyceride levels returned to baseline.

With the glucose load, blood sugar levels dropped backed to baseline in about 2hrs (actually blood sugar levels dropped even below baseline). I think a lot of us may notice we are hungry again about 2 hrs, maybe 3 after a bolus of carbs. For example, that morning bowl of cereal gives you a jolt for about 2hrs and then as blood sugar drops 2hrs later you definitely will be hungry. Same story with pasta or a huge hero for lunch.

On the other end, with the fat load, it took about 8hrs to for plasma triglycerides to return to normal levels.

So this displays that eating carbs is going to make most of us hungrier sooner than fats will. I think the carb-rich diet is why most Americans eat every 2hrs (6-11x) per day. So carbs for the most part are “fast” and go through us in the matter of 2 hours leading to us thinking about our next meal or snack.

2- Carbs stimulate the major hunger hormone above baseline.

Another study added to the “short-lived satiety effect” of carbs. In fact, they cause something known as bi-phasic hunger . Meaning, they reduce hunger for a few hours and then baamm you’re starving. Think about any carb-rich meal you’ve had, you’re starving a few hours later. Cereal for breakfast? You can’t wait for lunch. Pasta for lunch? You’re lucky to make it to dinner without a snack. Huge bed of rice with bread for dinner? You’ll definitely want dessert.

If you look below, carbs suppress the major hunger hormone ghrelin in the short-term, actually even more than protein & fats. However, by minute 200 ghrelin levels rise above baseline.

**As we see over the course of 6hrs protein is the most filling, followed by fats and lastly by carbs (which actually increase hunger above baseline!!)

“Ghrelin levels decreased in the initial 3 h, followed by a marked overshoot to above the pre-ingestion baseline during the second 3 h. No such overshoot occurred after protein or lipid ingestion, both of which suppressed acyl and total ghrelin levels until study completion(B).

  

Anyways~ if you’re a carb-addict or someone who feels “more hungry” after eating carbs, you will be much more fill (and long-term more at peace) by following a lowerish carb diet. Carbs aren’t the devil, but if they make you ravenously hungry all day long, it’s not going to work. This doesn’t mean you have to be zero carb but you should primarily get your carbs from vegetables, low-sugar fruits and the occasional potato if you’re someone who falls apart with carbs (like a lot of people do). This is also why I like the protein-rich diet as it makes you predominately eat protein + fats together. For example, eggs, steak, salmon, etc are high in protein and also fat so they have long-term potent effects on satiety. Throw any of those foods next to vegetables and you’ll actually be full for quite some time.

As a small side note, I think some people can get away with a moderate portion of carbs once per day (say at the tail end of dinner) because they avoid the hunger spike 3hrs later by being asleep. I think this may be another benefit of only eating carbs once a day, with dinner, potentially (avoiding bi-phasic hunger by being asleep). So if you were to eat say a potato or two, I’d have it at the end of your dinner so you avoid the bi-phasic spike in hunger (as you’ll be asleep). Yet again, I’ve also seen some people eat carbs with dinner and parlay this right into dessert, so personal tailoring is needed.

This isn’t meant to be a post saying you can’t have carbs but instead pay close attention to your hunger. We eat when we are hungry, so if you eat foods that make you more hungry, you’ll realistically only eat more long-term and gain weight. On the other end, if you eat foods that make you less hungry, you’ll eat less naturally later and most likely lose weight/fat.

Protein & Fats are better at reducing hunger long-term,

Carbs aren’t the devil but a lot of us will have to be careful (esp if they just make us hungry)

Refs:

(A) Cianflone, K., et al. "Metabolic response of Acylation Stimulating Protein to an oral fat load." Journal of lipid research 30.11 (1989): 1727-1733.

(B) Foster-Schubert, Karen E., et al. "Acyl and total ghrelin are suppressed strongly by ingested proteins, weakly by lipids, and biphasically by carbohydrates." The Journal of Clinical Endocrinology & Metabolism 93.5 (2008): 1971-1979.