Our good friend the Food Babe has published an interesting piece of pseudoscience writing entitled ‘Are Natural Flavors Really That Bad? (MUST WATCH)’. If you’re looking for the quick answer to this superfluous, click-bait title, let me tell you that it’s no: natural flavours are perfectly safe and healthy. But if you’re looking for an explanation of how taste actually works (and why her claims about natural flavours are utter nonsense), then please read on!
Vani Hari bases her distaste for natural flavours off the idea that “flavor in nature doesn’t come without nutrition.” Regrettably I’m here to tell her that this is unequivocally false. Hari thinks that “foods naturally taste amazing to us because they contain the nutrients we need. Flavors are the cue that tells us where to and the nutrients we need”. Not quite, Babe. Taste =/= nutrition. There are poisonous things that taste great, and very healthy foods that taste awful.
Following this same logic, she also believes that food companies add natural flavour to foods to “trick consumers into thinking they are getting nutrition that isn’t there.” Now, for once, this idea isn’t exactly wrong, but it is misleading. Food producers definitely do add natural flavours to all kinds of foods, but they do so in general to make things taste better, not to make them seem healthier. Think about it, do you really think your soda is healthier if its blueberry flavoured instead of cream soda? Doritos list natural flavours on their label, presumably those are natural flavours of tomato and cheese, but did you really think that Doritos are good for you like homemade tomato soup with cheddar on top?
Following your tongue to guide your diet probably isn’t a good idea, but I think we all knew that. If I only ate what I was craving, I’d live off of French fries, and I don’t think that’s because my body needs a lot of sodium and no protein. Besides, what tastes good is fairly subjective, but what’s healthy isn’t.
So what is flavour, if not nutrition? It’s all chemistry. We taste things because of interactions between the chemicals (gasp!) in food and the chemoreceptors in our mouths. You know how they say there are only 5 tastes: sweet, sour, salty, bitter and umami (savoury)? That’s a result of the taste receptorspresent in humans.
Salty and sour tastes are the simplest in many respects. Saltiness is detected by sodium ion channels in our tongues. When sodium ions (usually from sodium chloride or table salt) interact with these taste receptors, they are allowed to enter the cell. Being positively charged, they change the voltage inside the cell, which starts the process of sending an electrical signal to your brain that tells it, ‘hey, this tastes salty’. Sour tastes use a similar process, but with hydrogen ions entering sour taste cells.
The other 3 tastes are a bit more complex in how they’re detected. Instead of ions entering receptors directly and starting the signal to the brain, various molecules (depending on the taste) interact with different G-protein-coupled receptors. This interaction begins a whole pathway of signaling that eventually reaches the brain to convey taste. Many different molecules may activate these: for sweet tastes, it’s commonly sugars and molecules similar to sugars; for bitter, it’s more than 670 compounds; and for umami, it’s salts ofglutamic acid, the most commonly encountered of which is monosodium glutamate (MSG).
So food produces a taste because of the molecules inside of it, but why does it taste good? Because of physiology!
Our body does use the tastes of foods to get us to eat varying amounts of them, but not because of their nutrient contents like Hari thinks. In general, we find salt to be a pleasant taste because it is necessary to maintain homeostasis. Without salt, our kidneys would cease to function, so in an attempt to get us to ingest it, our brain makes it taste ‘good’.
Sugar, similarly, is absolutely integral to life. Carbohydrates are just chains of sugars and they are rich in calories, so they are desirable for a body that needs energy, hence the enjoyment that sweet tastes elicit. Umami tastes ‘good’ to encourage us to eat necessary fats and proteins.
Both salty and sour tastes are only ‘good’ in certain quantities. This is thought to be a result of evolution, since things that taste too acidic or salty tend to be spoiled, unsafely acidic or not ripe.
Bitter tastes bad to all humans naturally: just try to feed dark chocolate to a baby if you need proof of that, and it’s only through repeated consumption and some trick psychology that we come to enjoy bitter things. This is anevolutionary development due to many poisonous compounds tasting bitter, and why most medicines still taste bitter to us (our bodies think they’re poisons).
Now, there are many exceptions to these broad generalizations of what tastes ‘good’, proven in the fact that some (silly) people dislike dark chocolate, or the fact that I hate papaya, despite it tasting sweet. And in the modern world, as Food Babe warns us, there are artificial and natural flavours added to foods, so, surprise, surprise, there’s more to a healthy diet than just flavour.
Some good example include nightshade, which is incredibly toxic to humans, yet tastes quite sweet (making it even more dangerous to children who may ingest it), and apricot kernels which are quite toxic (as few as 10 of them could kill a child) due to their amygdalin content (this compound is metabolized into cyanide inside humans). But if you want to follow Vani’s logic, some people think they taste quite good, so they must be good for you, right?
Vani might be technically right about natural flavours being added to foods, but she’s wrong about why, and she’s wrong about a few other things too:
She says that “the flavors that humans love in tomatoes are synthesized in tomatoes from essential nutrients like beta carotene, amino acids, and omega 3’s”. Well, beta carotene is not an essential nutrient in humans, and indeedonly 9 of the 20 amino acids are. Studies on tomatoes have determined that there are about 27 compounds that contribute to their taste, 3 of which (geranial, 2-methylbutanal, and 3-methyl-1-butanol) actually influence how sweet a tomato tastes, regardless of sugar content (or ‘trick your brain!’ as she would say). So if the Food Babe believes compounds that alter how foods taste without altering their nutritional content are problematic, she should probably give up bruschetta.
Not to mention she claims that “soda without flavors is just carbonated water and sugar. No one would drink that without the flavor”’ somehow forgetting that the carbonated water industry is huge, and that billions of people do just that.
To recap, flavours are just the result of chemistry, things that are good for us do taste good, sort of, but not because of their nutrient content, and no one thinks that gummy bears are healthy just because they taste kind of like fruit.
So instead of asking yourself, “Did someone engineer this to be delicious or did nature engineer this to be delicious”, as Hari advises, I think I’d rather contemplate why it is I’d be taking diet advice from a blogger without a science degree.