Peanut butter indulgence - eating beyond the breaking point

In honor of the Breaking Bad finale (boo), MOH and I made a special dinner of mushroom risotto and decided to indulge in one of our favorite things to snack on: peanut butter. MOH made peanut butter cookies with little cacao nibs inside - so delicious. We were worried about the cookies being too rich or dry, but these cookies were moist, had the right amount of peanut butter, and best part: were tasty! Most peanut butter cookies can be made without any flour and consist primarily of three ingredients: peanut butter, sugar, and an egg. MOH's rendition of these cookies have a slight modification of sugar, cacao nibs (for a crunchy texture), and baking soda.

Ingredients:

1 cup peanut butter

1/2 cup truvia 

1 egg

1/4 cup cacao nibs

1 tsp baking soda

Protocol:

1. Preheat oven to 325°F. Line baking sheet with parchment paper

2. In a mixing bowl, mix all ingredients until smooth. Chill dough in refrigerator for 30min

3. Using hands, roll dough into 1" balls and space ~1" apart on the parchment paper. Flatten with a fork

4. Bake for 8min in the oven. Cool on the baking sheet (not a cooling rack).

5. Eat them all! 

These cookies are addicting. The recipe makes 36, but now, there's only 9 sad cookies left on the rack. I'm full, yet I'll eat a cookie nonetheless. I'll sport my cookie belly, run for a few more minutes, just to console myself that eating that extra cookie is worth it.

Rat that's had one too many crackers! (Photo courtesy of J. Servaes)

This week in Science, researchers published some really cool stuff on what motivates feeding behavior, whether an animal is starved or satiated. In a nutshell, researchers manipulated a pathway in the brain that is responsible for mediating feeding and observed how activation or inactivation of the pathway affected whether a rat would go for food. What they found was activation of the pathway led the rat to eat more, even when the rat was full . Conversely, inactivating the pathway led rats to eat less, even if rats were starved. For more science, scroll down to *.

Pretty crazy stuff, considering activation of a particular pathway in the brain can induce eating beyond satiation in an animal. According to this article, this is the first identified pathway that can modulate feeding behavior.

One thing that comes to mind is how many of us will reach for those extra cookies or chips even though we're way full off dinner. I think an interesting direction to go would be if this pathway mediates all types of feeding behavior or if there's a differential pathway for fatty foods, salty foods, sweet foods.

*
In this article, researchers investigated the pathway that has been implicated towards dictating feeding behavior. This pathway of the brain is called the the bed nuclei of the stria terminalis (BNST) and the lateral hypothalamus (LH). The cells in the BNST that connect to the lateral hypothalamus are primarily gabaergic inhibitory cells.

In this study, researchers used optogenetics (a method to modulate brain activation or deactivation by stimulating light on the brain region) to activate or block the pathway from the BNST to the LH. Specifically, they targeted the cells that projected from the BNST to the LH and looked to see whether rats would preferentially go to the corner of a room that either had food or was empty. Upon stimulation of this pathway, rats would preferentially go to the food corner.

In a separate test, they wanted to see if behavioral output would be changed if the rats were either full or starved. Even when rats were full, stimulation of this pathway caused the rats to continue consuming the food. In contrast, rats that were starved would not consume food if they inactivated the BNST-LH connections.



Reference:
Jennings JH et al., 2013. The inhibitory circuit architecture of the lateral hypothalamus orchestrates feeding. Science. 341(6153): 1517-21.