DAY 3: Why Are salt, sugar and fat so addictive?
“The food industry is not only generating billions of dollars for itself by designing hyperpalatable combinations of sugar, fat, and salt – it’s also creating products that have the capacity to rewire our brains, driving us to seek out more and more of those products.”
– David A. Kessler, MD, former U.S. Food and Drug Administration Commissioner
Why are salt, sugar and fat so addictive?
My husband and I approach food from very different perspectives. I have no doubt my approach seems a bit wacko to him sometimes, but likewise there are times I’m convinced he’s from another planet. For example, this common situation:
[Scene: a restaurant with actual tablecloths]
“Would you like to see the dessert menu?” our waiter inquires.
“Oh no, I couldn’t possibly! I’m stuffed!” Rob exclaims, rubbing his stomach making obvious how full he is.
[I look at him, as if finally seeing him for the alien life form he obviously is.]
“Who eats dessert because they’re still hungry?! Of course we want to see the dessert menu,” I say with a little too much desperation in my voice.
[Waiter slinks off, confused and slightly terrified]
In his book Salt Sugar Fat: How the Food Giants Hooked Us (2013) Pulitzer Prize-winning author and New York Times investigative reporter Michael Moss writes extensively about how Big Food manufacturers (Nestle, Kraft, General Foods, et al) have teams of scientists, product developers, chemists, and marketers who are working hard to understand what drives us to buy (and more importantly crave) certain foods. Starting in the 1950s but exploding in the 1980s, food manufacturers began concocting processed foods that were increasingly so delectable, delightful, scrumptious and seductive as to make them addictive to some of us.
The companies engaged experts in brain chemistry, psychology, and sensory salience (how memorable and/or emotionally pleasing a food is) in their quest to design foods that trigger our brains’ reward centers. Even more, they began to understand how to cue our appetites before we are even conscious of our hunger, and learned to do so in a way that tapped into our emotional need for comfort and indulgence.
Each element of the salt / sugar / fat (hereafter referred to as “SSF”) equation plays an important part in this dance, according to Moss.
Let’s take a look at each element of the SSF equation independently:
You may have heard that sugar triggers the same chemical reaction in the brain’s reward centers (the hippocampus and amygdala), as does heroin or cocaine. Roughly speaking that is true. In the 1970s, in an effort to figure out how to get soldiers to eat more while suffering the duress of war (life-threatening stress is a major appetite suppressant), scientists discovered that when the soldiers’ MREs (Meals Ready to Eat) contained sugar, they were devoured while those without sweeteners went unfinished. Those same scientists began the brain research on how sugar affects our desire for food that ultimately landed in the hands of Big Food who then put it to use developing products that consumers couldn’t get enough of.
It is well known that humans have an evolutionary pre-disposition to prefer the taste of sugar. Newborns will show signs of preference for sugar above any other taste. Yet as appealing as sweets are, who empties a packet of sugar into their mouth and swallows with a sense of satisfaction? No, it’s sugar in conjunction with …
Fats give foods the mouthfeel and texture that we crave. It’s that gooey, sticky mouthfeel that’s in cheese, or the juiciness in savory meats, or the creaminess in cheesecake and ice cream. The list of enticing properties that fat lends to food is nearly endless. The food industry, meaning manufacturers of the processed foods that line grocery store shelves and pack mini-marts, and also the restaurant industry, refer to fat as “liquid gold.”
And it isn’t just the power of luscious mouthfeel and silky texture that fat imparts on our favorite foods; fat gives food tenderness, deepens its color, enhances good flavors (aromatics, sweet, salt) and masks bad ones (acid, bitter). Maybe most important of all, unlike sugar and salt, the brain has no saturation point for fat. It’s something food scientists refer to as the “bliss point,” beyond which foods taste too sweet or too salty, for example. But there is no bliss point for fat. And especially when fat is emulsified into other foods as it is in most processed foods, we don’t see it coagulating on the surface so our eyes, our tongues and our brains don’t recognize it as fat. We just ingest it along with the food we’re eating. But because of the high fat content, that food is calorically dense and BOOM! We consume more calories than we intended, and eventually we put on weight.
Of the SSF trifecta, salt is probably the most ubiquitous and the most pernicious. Salt is a mineral, obtained as salt water evaporates or found underground. The human body requires some salt for survival; it’s necessary for muscle function as well as digestion and absorption of the food we eat. It’s a critical electrolyte, which help carry electrical impulses through the body, aiding various bodily functions. Which is all well and good, until you get ahold of a handful (or ten) of kettle-cooked potato chips. (An aside: the Kettle Brand website promotes their chips as a “healthy snack” because they use all-natural ingredients. Cough, cough.) And of course it’s not just those chips; the average American adult consumes 3,592mg of sodium each day (according to the U.S. Department of Health and Human Services), though the recommendation is 2,300mg. In fact, federal data shows that a whopping 90% of Americans eat more than the recommended daily amount of sodium.
The health implications of all this salt are significant (hypertension, stroke), but why is it especially addictive? And why is it not enough to just stop adding salt to food? Turns out only 6% of the salt we ingest is salt we add to our food; the rest comes from processed and restaurant food. (To that point, the Hungry Man roast turkey dinner has 5,400mg of sodium. Holy high blood pressure, Batman!)
The fact that 94% of our daily sodium intake comes already packaged in our food is a problem for all of us, but if you have food addiction it’s especially problematic and here’s why: salt tastes good. I mean, really good. It enhances other flavors and makes them “pop.” Ever accidentally left the salt out of your batch of chocolate chip cookies? Yeah, they’re about as appealing as hockey pucks.
We will talk much more about the power of salt in the weeks to come, but I believe it holds the key to overcoming food addiction.
So why are salt, sugar and fat so darn addictive?
Again, Michael Moss:
“The blood gets especially besieged when processed food is ingested, flooding the system with its heavy loads of salt, sugar, and fat. But where the links between eating and drugs get really interesting is in the brain. There, narcotics and food – especially food that is high in salt, sugar, and fat – act much alike. Once ingested, they race along the same pathways, using the same neurological circuitry to reach the brain’s pleasure zones, those areas that reward us with enjoyable feelings for doing the right thing by our bodies. Or, as the case may be, for doing what the brain has been led to believe is the right thing.”
– Salt Sugar Fat, page 276
So no, it’s not your imagination. Big Food and your own biochemistry are powerful forces working hard to keep you hooked on SSF. Understanding the how and why of that is the first step to overcoming food addiction.
More tomorrow. Until then, stay strong.