Posted by Eric Troy on 04 Nov 2015 21:32
A typical article about food cravings on a website called Daily Transformations claims that food cravings are your body's way of telling you what it really needs.
It is a long-held belief.
Many people are convinced that when they crave a particular food, it is because that food contains a certain nutrient, or set of nutrients, that the body needs.
The article linked above goes so far as to suggest that a variety of oft-craved foods and beverages, such as coffee, are the body signalling a need for nutrients, and so these cravings can be satisfied by substituting a food or foods that is a good source of the nutrients associated with this craving.
It seems quite obvious to most people addicted to coffee that caffeine must have a big hand in their cravings, but the logic breaks down at a fundamental level.
Let's look at some of the suggestions from the article:
- Chocolate cravings: a signal that your body really needs magnesium. Substitute raw nuts, seeds, beans, and fruits.
- Sweet cravings: Craving sweet foods means you need chromium, carbon, phosphorus, sulfur, and tryptophan: A large variety of other foods should be eaten instead.
- Bread and toast craving: Your body needs nitrogen. Eat high protein foods.
- Coffee or Tea: You need phosphorus. Eat chicken, beef, liver, fish, eggs, etc. instead.
- Alcohol and drugs: You need protein.
- Tobacco and overeating in general: silicon.
We can stop there. At a glance, there are some obvious problems. One is that carbon, although it is abundant in the body, is not a nutrient. Neither is nitrogen, although it is abundant in protein rich foods. In fact, although the most abundant element in the body is oxygen, which makes up about 63% of its mass, the body contains around 18% carbon, and 3% nitrogen. Add hydrogen, at around 9%, and you have the mass of most of your body. These elements are found in proteins, carbohydrates, and lipids, meaning that they are widespread in the food we eat.
Silicon is claimed to be what your body needs when you crave tobacco, or when you simply overeat in general. The body contains silicon in minuscule amounts, and silicon is found in the foods we eat, especially plant foods. However, while it is possible that there is a physiological role for silicon in the body, at very small amounts, Silicon is known to be an essential nutrient in certain animals, but its role in humans is still under study.we are not sure what it may be.
Regardless, what the article fails to resolve is why, if these cravings are a signal that your body needs these nutrients, the body does not crave foods high in these nutrients. When I wake up in the morning I don't want to eat a chicken breast, I want a cup of coffee. Even if I eat eggs (a supposed substitute for coffee) I still want a coffee. At the end of a hot day I want a beer or a cool drink, not nuts and blueberries.
Alcoholic beverages contain no protein. Why would your body crave alcohol when it needs protein? This is, of course, to say nothing of the obvious: We know the mechanism behind alcohol cravings, just as we know why we crave coffee. We even have a very good idea as to why chocolate is so heavily craved! Obviously, the claims have not scientific underpinning, whatsoever.
Why Do We Crave Certain Foods?
Although we don't completely understand the underlying mechanisms in food cravings, the craving (more often than not) is for the flavour, the texture, or the refreshment, not the nourishment and it is probably mediated by a response in the brain associated with the eating of certain palatable foods.
Yet, should cravings for food be coupled with cravings for cigarettes, coffee, and alcoholic beverages, all of which contain known addictive drugs?1
Smokers crave tobacco because they are addicted to nicotine; they are not after nuts and red fruit. However, when nicotine alone is substituted for cigarettes, cravings are not always completely satisfied. There must be components beyond nicotine that mediate cravings for cigarettes, such as perhaps the ritual of smoking, and the pleasure associated with smoking. Do foods contain such powerful substances? Or is it just the pleasure?
The truth is that cravings are a mixed bag. The simplistic idea that your body always craves what you "need" is just that..simplistic. Yes, we have all craved things that are good for us, and usually after a long period of not having those certain things. But they ARE usually things we like and enjoy.
You are never going to crave something you hate even if it is the most nutritious food known to man and your mother made you eat it a million times.
So, there is nothing to support the assertions given on the page linked above. Is pie in the sky at best. What I would call wishful thinking!
Look at one of the most useful comments by readers of the article, by a Dr. Clark:
It a common misconception that you crave certain foods because of specific nutritional deficits but there is actually no data out there to support this claim. For instance, when you need vitamin C you don’t crave oranges you just get scurvy. Getting vitamin C then alleviates the scurvy. You crave sweets because they cause a spike in blood sugar and you crave tobacco, drugs, and alcohol because of a physical or psychological addiction in which case the substance that your body is missing is indeed nicotine, drugs, or alcohol (in the case of the physical addiction.) It is tempting to believe someone who makes a claim like this because it seems to make so much sense but nutrition is an impressive science now and you don’t have to be a doctor or scientist to learn more about it! All of this is information available to the public and is easily accessed through your computer! Also, although it is the basis of life on earth, “carbon” by itself (as in graphite and diamonds) is not a nutritional requirement of the body.
The author of course disagrees, and it seems this quite helpful comment may have been removed since published.
Do Cravings Ever Correspond to Bodily Conditions?
There are some instances where cravings seem to correspond to or are signals of a certain underlying physiological condition. Such as in anemia when people crave ice (to chew on) and odd things such as paper or clay. This is called pica (pronounced peeka). There is even something known as preganancy pica where a pregnant woman craves one or more hightly unusual non-food substances. However, just because scientists come up with a fancy name for something does not mean that we understand the underlying causes.
What is a Craving, Anyway?
One thing that we, as lay people, must understand, is that our use of the word craving is not necessarily the same as how it is used in a clinical sense. Although not everyone agrees on a precise definition of craving, as in, for instance, the craving for an addictive drug, it is certainly agreed that a casual 'food craving' is nowhere near the same as a craving for heroin!
If you and your buddy are sitting around playing video games or watching a movie, and your budy says "..you want to get something to eat?" You might reply, "Yeah, I have a craving for pizza." Let's say your buddy replies "I'd rather have Chinese."
"Okay, I could go for Chinese..," you respond. Clearly, your "craving" was more of a hankering than the craving a smoker might get for a cigarrette. So, one defintion of craving that probably should be agreed upon is that in a craving, whether for food or drug, the craving cannot be satisfied by any other means. In other words, when you really crave something, nothing else will do. You must have that thing!
Yes, there are certain foods that produce a response similar to this. People do get food cravings that they cannot resist. Chocolate is one of the foods that people most often crave.
Why Do We Crave Chocolate?
It should be clear that you do not crave chocolate because of a bodily need for nutritents, such as minerals or vitamins. However, might there be other substances in chocolate that produce a response, whether psychological or physical, which then produces cravings? Yes. Chocolate does contain substances that might have the potential to act pharmacologically, such as histamine, tryptophan, serotonin, phenylethylamine, and octopamine.
Here is the catch: There are plenty of other food which contain these substances in much higher amounts but which do not produce commonly produce such cravings. Perhaps the sugar in chocolate, which may produce a spike in blood sugar, is responsible, similar to what Dr. Clark suggests in the comment above? Well, then, why chocolate. When someone truly craves chocoate, gummy bears will not do. In fact, cocoa powder contains all the substances named above, and yet a cup of hot cocoa generally does not satisfy chocolate cravings!
Explanations for Food Cravings
One thing is becoming increasingly clear: food cravings are mood-mediated. More people crave chocolate when their mood is low. They crave chocolate when they are stressed, sad, or depressed. People often also feel guilt associations after giving in to these cravings, which has to do with concerns about weight and body-image.
The actual sensory experience of eating chocolate, its taste and its mouthfeel, probably have as much to do with cravings for it as any number of other factors. High-sugar and high-fat foods tend to produce more cravings, and these cravings may be endorphin-mediated. We crave highly platable foods. When we eat these foods, endorphins are released. This calms us. Thus, when we are in stress, we turn to these palatable foods to calm us.
Is this the only explanation for food cravings? Probably not! But it is certainly more credible than the supposition that all food cravings are brought about by the body's need for a certain nutrient which that food contains.
Obviously, we crave coffee for caffeine. However, many life-long coffee drinkers report that while a caffeine pill might help a little, and stave off the inevitable caffeine headache from a lack of coffee, caffeine alone does not completely satisfy coffee cravings. When we want coffee, we want coffee. Coffee contains many other substances which may be associated with cravings, but the taste and experience of drinking coffee may still be important.
Unlike coffee, a lifelong "addiction" to which we can trace to the physiloligical affects of caffeine, many cravings are not due to addictions.
Do Food Cravings Mean You Have a Food Addiction?
Today, when we are inundated with so much information about our many addictions to sugar, fat, etc., this is important to understand. Sometimes a craving is just a craving. That is, sometimes you just have a simply desire for a food that you happen to enjoy.
Yes, food cravings do have to do with the brain, but being addicted to alcohol and quitting cold turkey can result in horrible withdrawal and even death. Detoxing from other drugs will cause similar suffering. Such a withdrawal does not seem likely for someone 'addicted to chocolate.'
Yes, food cravings, like drug cravings, may be related to reward mechanisms in the brain. But, this does not mean that everyday cravings are similar to drug cravings! Indeed, there may be a reason that the foods we enjoy are associated with positive reward mechanisms in the brain. These foods tend to be energy rich, a more overriding factor in the past than in today's affluent times, when people have the luxury of choosing foods for a myriad of reasons.
These same mechanisms may lead to more intense and chronic cravings that involve food-binging and compulsive over-eating. However, the idea that anyone who experiences food cravings based on pleasure is doomed to such behavorial patterns. While most people do occassional crave certain foods, not everybody is prone to disordered eating.
Messages such as "food cravings are your body's way of telling you what it needs" are attractive, as they counter doom and gloom messages that are so abundant today. A feel-good message that tells us that our body knows what it is doing, and we can learn from our cravings, rather than try to control them, and that this can lead to better health, is bound to attract many believers. However, the reality of food cravings lie somewhere on a continuum between "tasty food is addictive" and "your body craves what you need."
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