Friday, March 29, 2013

Food Reward Friday

This week's "lucky" winner... milkshakes!

Milkshakes are finely crafted from a food reward perspective: sugar, emulsified fat, a pleasant cold sensation, and a nice mild flavor, with no chewing or fiber to slow down ingestion or digestion.  People readily add a milkshake on top of a filling meal because it does not contribute to satiety in proportion to its calorie content.  

The combination of emulsified fat and sugar is particularly rewarding: think chocolate and ice cream.  Recently, I was in Palm Springs and I visited one of the oldest and most productive date farms in the country, Shields Date Garden.  They're known for their delicious date milkshakes.  When in Rome...  I have to say, not having had a milkshake in years, it was incredibly good.  The second the milkshake hit my tongue, the flavor was so intense I felt a strong desire to keep drinking, which is what I did until it was gone.  The desire for another milkshake kept popping into my mind over the ensuing days, demonstrating the pull that these foods can have on our subconscious minds.  It was definitely one of the most hyperpalatable/rewarding foods I've ever eaten.  

Thanks to NickSS for the photo (via Wikipedia)


Robert said...

Hi Dr. Guyenet,

Do you think the additional additives in a typical fastfood strawberry milkshake you listed in your TED talk enhance the palatability of the shake relative to a homemade milkshake with less ingredients?

Thank you for the very interesting blog. (and I am not a Dr. yet...).

stevetursi said...

I've been to Shields. Those milkshakes are particularly rich & heavy.. One 16-oz is enough to make you feel full the rest of the day. In fact my wife and son couldn't finish their's.

bongo said...


Why do you think you have these intense food cravings for the milkshakes and fine pastries?

I can tell you not everyone does and when they do they are on a spectrum, i.e. crushing 5 milkshakes as opposed to having a few sips of one.

Many would say one who has such cravings is seriously lacking some nutritional element to their diet - to few calories, low minerals vitamin deficiency etc.

I can tell you when I really focus on eating the right amount of the right kind of stuff I can pretty easily not even be tempted by most stuff like cake, candy, cookies, chips as in I don't even want to eat them on any level. But if I miss a few nights good sleep, skip meals, work out too much, eat junk like such as subway sandwich, the cookies are calling me!

Incidentally, I don't see all that much harm in a milkshake made with high quality cream (without carragenan, very important!) and low to moderate sugar. In the context of a highly nutrient dense diet with sufficient calories, I don't believe anyone is going to want to over eat milkshakes or anything else.

Stephan Guyenet said...

Hi Bongo,

I don't crave pastries and milkshakes. I simply feel tempted by them if they're right in front of me, just like almost everyone does. There's no evidence this has anything to do with a nutrient deficiency (that idea is Internet woo). It has to do with the sensory properties of the food.

Dan said...

When I was on a stricter version of paleo I have intense cravings for ice cream. Always ice cream. I guess I could put milkshake into that category but I have always wondered why?

Sabine said...

Having been on a ketogenic diet for a few years, I find sweet tastes revulsive, and not at all rewarding.

Sweet foods, especially drinks, give me immediate severe stomach and headaches, besides other serious and unpleasant symptoms. This is NOT very rewarding!

Scott W said...

Sensitivity to palatability varies among individuals. People who feel full after half a shake (like my wife) just cannot understand those of us who finish it off and want another, with no countervening signal to stop...not even extreme fullness to the point of discomfort.

It is impossible to make something too sweet for me to eat.

My rule of thumb (often broken): If I know that I'll want more of something after a single portion, then I can't have it. If it do eat it, I'll want more of it for days, even weeks, depending upon how palatable the food was.

All kinds of things fall into this category that for most would not be all that rewarding, such as grapes.

Scott W

Unknown said...

I have a milkshake whenever I want. Always a really good one too. I don't think about them very much and get them mainly when I've been working out and have been a bit busy and need to get some extra calories in.

The bacon toffee one here at the Little Goat is great for that. But wonder if this has to do with variations in fat taste receptors? I actually find there can be too much milkshake for me even if it's good. I took my last one home because I couldn't finish it.

luckybastard said...

"It was definitely one of the most hyperpalatable/rewarding foods I've ever eaten."

Or as I like to call it, a DAMN fine milkshake.

As a recovering fatty, I've found that if I indulge in these goodies, I have to do it while out and about and with a finite quality. Otherwise, it gets ugly fast.

Laura said...

I am curious as I have seen this come up almost every Friday when there is a Food picture posted. Someone invariably says "Oh I don't find that food tempting at all". While I definitely understand the distinction between cravings and temptations, for many people, the point you are making about hyper-palatability doesn't seem to apply. Is that something you cover in your research, different temptations for different people, and why that is?

Sabine said...

Yes, Betsy, I used to be like this.
I guess, I got over my addiction to sugar by avoiding it for long enough. (it took a couple of years to start finding it disgusting.)

This is the reason, I always failed with these diets, that allow you a REWARD day. Give an alcoholic an ounce of booze and he will drink a barrel, if available. Give a sugarholic a cookie and he will buy up the store's supply, if he has the money.

I will not tempt fate and try to get myself used to it again. I stay away from all sweet tastes and eat real food instead. I do not miss anything.

TCO348 said...

A response that comes up over and over about these highly rewarding foods is that any strong motivation to eat these foods must be motivated by some nutrient deficiency. This seems very unlikely. If it were motivated by a nutrient deficiency it seems the craving would be more specifically directed at a group of foods that contains some particular nutrient.

When this topic comes up I am always left to wonder about the evolutionary purpose of these desires. An overweight person doesn't need more stored body fat. However, the desire to eat foods that will increase the amount of stored body fat doesn't go away when one is overweight. I tend to think this is adaptive. Stefan, I wonder if you could comment on this. What I am thinking is that our evolutionary response to food that has all the characteristics of calorie density, is that of increasing our storage capacity so as to take advantage of what would have been a rare opportunity to store lots of body fat in a short period of time. If such a cache of calorie rich food were rarely encountered there would have been very little downside to this. So perhaps the tendency to consume large amounts of this calorie rich food and to store it was adaptive. The other explanation is that its not adaptive, its just that food like this was never encountered in our ancestral environment and so some of us don't respond to it well and we eat way too much of it.

TCO348 said...

Stephan, not Stefan. Sorry about that.

Unknown said...

Milkshakes are energy drinks we can have them whenever we like. So nothing to worry just go for it.

Sanjeev said...

> must be motivated by some nutrient deficiency

yes, evolutionary pressure produced an organism that on some level "knows" it is in deficiency,

AND made that organism eat more


made that organism eat MORE OF WHAT PRODUCED THE DEFICIENCY (aka "fattening foods")


made that organism such that it is NOT driven to extraordinary efforts to seek out different foods that have a chance of remedying the deficiency
makes a lot of sense.

Jane said...

Stephan, I don't expect your wanting milkshakes/pastries is anything to do with nutrient deficiencies, but I'm not sure this idea is internet woo. Remember Roger Williams' finding that rats on a typical American (micronutrient depleted) diet ate much more of the sugar they were offered than rats on the same diet supplemented with micronutrients?

I think this experiment should be repeated, with a view to finding out which micronutrients are responsible.

mbw said...

I used to have this reaction to milkshakes (and well most foods really), but since I started lifting heavy weights 3-4 times a week and purposely eating 150g of protein per day (which is 1g per lb of bodyweight), I don't have that issue with anything at all anymore. In fact I frequently have to force myself to eat my goal amount of calories this way. After I get a a minimum of 150g protein and 100-200g carbs per day, the rest are free calories and my nights frequently end in force feeding myself a few spoonfuls of peanut butter :) This is from someone who used to be overweight and hungry all the time, sometimes even hungrier after a meal than before it.

Unknown said...

I agree with you Dr. Guyenet! There are countless times that I craved and consumed milkshakes especially when I am having an intense diet. I know it can ruin my program but I can't control my cravings. Even now, I can still imagine milkshakes with fruit syrup and chocolate sauce. It is really rewarding!

Atherine Elizabeth Alexandria said...

I think this experiment should be repeated, with a view to finding out which micronutrients are responsible.