Skip to main content

Verified by Psychology Today


Beating Stress

Food for mood is scientifically established.

As I was walking past the Vitamin section of CVS, I heard the word serotonin pass between a young man and a saleswoman. “I can’t find any 5HTP on the shelf,” he was telling her, “…You know, the stuff that makes serotonin? I need some for stress!” She peered at the supplement stocked shelves and nodded. “We must be all out,” she responded. “But there is a health food store a few blocks away. Maybe they have some.”

I casually wandered over and uninvited said, “You know, you would feel less stressed and more relaxed just by eating a potato. You don’t have to take supplements for your brain to make serotonin, so why go to a health for store for 5HTP? Your brain makes serotonin every time you eat pretzels or potato, or any other starchy carbohydrate. “

He listened to me patiently, although I suspect he was humoring some crazy lady wearing tennis shoes (actually I had just come from the gym and was wearing sneakers).

“But isn’t it better to take the supplement?” he asked.

“The problem with 5HTP is that taking it to make serotonin is unnatural. The brain normally makes serotonin from what you eat. Now if you were to buy that bag of pretzels (I pointed to snacks in the adjacent aisle) and eat them, you would have more serotonin in your brain within a half an hour.”

“You mean my brain makes serotonin after I eat a snack?” He looked at me as if I was really some weirdo roaming around CVS telling bizarre stories.

Obviously this was neither the time nor place to give him a lecture on the neurochemistry of serotonin synthesis. So I quickly mentioned how after carbohydrates are eaten, insulin allows tryptophan to get into the brain and this turns into 5HTP and then serotonin.

“There are no side effects from eating carbohydrates, but 5HTP certainly has a few, like drowsiness and nausea,” I added

He nodded and mentioned that 5HTP makes him so drowsy it is hard to work, and he worries about driving. He left the store carrying the pretzels, but I wonder if he also stopped by the health food store to get some 5HTP, just in case the lady with the sneakers was indeed crazy.

As I walked back home, I mused on how typical it is for people to bypass food in favor of herbs, supplements, teas, minerals, and special potions no doubt prepared in big cauldrons by witches. A friend told me that he has given up eating carbohydrates, but takes magnesium and alcohol when he needs to relax. Pointing out that magnesium is only a muscle relaxer as well as that alcohol has more calories per gram than carbohydrates, and its own share of side effects, was useless. He simply did not want to hear what he did not believe.

And of course there are so many others whose dietary advice is simply make-believe. These are the proponents of diets that eliminate carbohydrates, or curtail their intake. These diet gurus make believe that serotonin can be made without eating carbohydrate, or refuse to acknowledge that the bad moods, aggression, anxiety, depression and insomnia following such diets is not due to vanishing brain serotonin.

Isn’t it time to go back to eating the way nature intended us to do? We evolved eating carbohydrates, and our brains responded by making serotonin. Even though 5HTP is found naturally in the seeds of the African plant, Griffonia simplicifolia, myths and folklore are not filled with tales of people roaming around the continent seeking out the seeds of this plant to attain tranquility and relief from stress. Yes, do Google this plant name to see it's purported effects on libido. I have potatoes to write about.

Mystifyingly, we resist believing that the natural way to make more serotonin is to eat carbohydrates. And that is understandable because it doesn’t seem to make sense. Carbohydrates don’t contain tryptophan, or indeed any amino acids. Eating protein, which is made of amino acids, prevents tryptophan from entering the brain. Isn’t nature sometimes counterintuitive?

Apparently not. More than 30 years ago, two scientists at MIT discovered the connection between eating a potato, pretzels, or a tortilla and serotonin synthesis. There is a barrier between the bloodstream and the brain that monitors what does and does not enter the brain. When certain amino acids try to enter the brain, they must pass through specific gateways. Tryptophan shares an entrance area with five other amino acids that are more abundant in protein and the blood than tryptophan. After protein is eaten, digested amino acids “clog” the gateway to the brain, and the small number of tryptophan units are outnumbered by the larger number of the other amino acids. As a result, very little tryptophan gets into the brain.

When carbohydrates (i.e. a small bag of pretzels) are eaten, insulin is released and sends the amino acids that compete with tryptophan out of the blood and into the cells. At the same time, tryptophan is able to enter the brain easily because the competing amino acids are no longer crowding the gate. If my fellow shopper had eaten his pretzels on the way back to work, soon after they were digested tryptophan would be entering his brain and new serotonin taking away his stress.

But resistance toward eating carbohydrates to relieve stress, and experience the other benefits of sufficient serotonin such as satiety after eating and increased focus, is also based on the effect of excessive carbohydrate intake, especially sugar, on heart disease, obesity and maybe cancer. An excess of anything, even water, is bad. Fortunately, research has also found that only small amounts of carbohydrate have to be eaten to make serotonin. Twenty-five to 30 grams of carbohydrate—the amount in one cup of Cheeriosis sufficient. And if the carbohydrate is a starchy and very low-fat like breakfast cereal, or popcorn, pretzels or rice crackers, natural tranquility comes at a price no one should resist.

More from Judith J. Wurtman Ph.D.
More from Psychology Today