You can satisfy simple hunger with almost any food, but cravings for something in particular can fix us on a certain product until we finally manage to eat it.
Most of us know what it’s like to have food cravings. Typically, cravings occur for high-calorie foods, so they are associated with weight gain and an increase in body mass index.
It is widely believed that food cravings are our body’s way of signaling to us that we are lacking in a particular nutrient, and in the case of pregnant women, that cravings are signaling what the baby needs. But is it really so?
Most of the research has shown that food cravings can have multiple causes – and they are mostly psychological.
In the early 1900s, Russian scientist Ivan Pavlov realized that dogs wait for treats in response to certain stimuli associated with feeding time. In a series of famous experiments, Pavlov taught dogs that the sound of a bell meant feeding time.
According to John Apolzan, assistant professor of clinical nutrition and metabolism at the Pennington Center for Biomedical Research, a lot of food cravings can be explained by the environment you’re in.
“If you always eat popcorn when you start watching your favorite TV show, your popcorn cravings will increase when you start watching it,” he says.
Anna Konova, director of the Addiction and Decision Neuroscience Laboratory at Rutgers University in New Jersey, notes that mid-day sweet cravings are more likely to occur if you’re at work.
Thus, cravings are often due to certain external cues, not because our body is demanding something.
Chocolate is one of the most common cravings in the West, which supports the argument that cravings are not due to nutritional deficiencies, as chocolate does not contain large amounts of those nutrients that we may be deficient in.
It is often argued that chocolate is such a common object of desire because it contains high amounts of phenylethylamine, a molecule that signals the brain to release the beneficial chemicals dopamine and serotonin. But many other foods we don’t crave as often, including dairy, contain higher concentrations of this molecule. Also, when we eat chocolate, enzymes break down phenylethylamine so it doesn’t enter the brain in significant amounts.
Studies have found that women are twice as likely to crave chocolate as men, and most often this occurs before and during menstruation. And while blood loss can increase the risk of certain nutrient deficiencies, such as iron, scientists note that chocolate won’t restore iron levels as quickly as red meat or dark leafy greens.
One would speculate that if there was any direct hormonal effect causing a biological craving for chocolate during or before menstruation, that craving would decrease after menopause. But one study found only a small decrease in the prevalence of chocolate cravings in postmenopausal women.
It’s much more likely that the link between PMS and chocolate cravings is cultural. One study found that women born outside the US were significantly less likely to associate chocolate cravings with their menstrual cycle and experienced chocolate cravings less frequently compared to those born in the US and second-generation immigrants.
The researchers argue that women may associate chocolate with menstruation because they believe it is culturally acceptable for them to eat “forbidden” foods during and before their period. According to them, there is a “subtle ideal” of female beauty in Western culture that gives rise to the notion that a strong craving for chocolate should have a strong justification.
Another article argues that food cravings are associated with ambivalent feelings or tension between the desire to eat and the desire to control food intake. This creates a difficult situation, as strong food cravings are fueled by negative feelings.
If those who limit themselves to food to lose weight satisfy cravings by eating the desired food, they feel bad because of the thought that they violated the diet rule.
It is known from research and clinical observations that negative mood can only increase a person’s food intake and even provoke overeating. This model has little to do with the biological need for food or physiological hunger. Rather, they are the rules we make about food and the consequences of breaking them.
Research also shows that although chocolate addiction is common in the West, it is not at all common in many Eastern countries. There are also differences in how beliefs about various foods are communicated and understood—only two-thirds of languages have a word for craving, and in most cases that word only refers to drugs, not food.
Even in those languages that have analogues for the word “craving”, there is still no consensus on what it is. Konova argues that this hinders understanding how to overcome cravings, since we can label several different processes as cravings.
Manipulation of microbes
There is evidence that the trillions of bacteria in our bodies can manipulate us into craving and eating what they need—and it’s not always what our body needs.
“Microbes look after their own interests. And they are good at it,” says Athena Aktipis, assistant professor of psychology at Arizona State University.
“Intestinal microbes, which survive best in the human body, become more resilient with each new generation. They have the evolutionary advantage of being able to influence us more to make us feed them according to their desires,” she says.
Different microbes in our guts prefer different environments—more or less acidic, for example—and what we eat affects the ecosystem in the gut and the conditions in which the bacteria live. They can get us to eat what they want in several different ways.
They can send signals from the gut to the brain through our vagus nerve and make us feel bad if we don’t eat enough of a certain substance, or make us feel good when we eat what they want by releasing neurotransmitters like dopamine. and serotonin. They can also act on our taste buds so that we consume more of a particular food.
Scientists have not yet been able to capture this process, Actipis says, but the concept is based on their understanding of how microbes behave.
“There is an opinion that the microbiome is part of us, but if you have an infectious disease, of course you will say that microbes attack your body, and are not part of it,” Aktipis says. “Your body can be taken over by a bad microbiome.”
“But if you eat a diet high in complex carbohydrates and fiber, you will have a more diverse microbiome in your body,” Aktipis says. “In that case, a chain reaction should start: a healthy diet breeds a healthy microbiome, which makes you crave healthy food.”
How to get rid of cravings
Our lives are full of food craving triggers, such as social media ads and photos, and it’s not easy to avoid them.
“Wherever we go, we see advertisements for products with a lot of sugar, and they are always easy to access. This constant attack of advertising affects the brain – and the smell of these products causes cravings for them, ”says Avena.
Since the urban lifestyle does not allow avoiding all of these triggers, researchers are studying how we can overcome the conditioned craving model using cognitive strategies.
A number of studies have shown that attention training techniques, such as being aware of cravings and avoiding judging those thoughts, can help reduce cravings overall.
Research has shown that one of the most effective ways to curb cravings is to eliminate the foods that cause cravings from our diet—contrary to the assumption that we crave what our body needs.
The researchers conducted a two-year trial in which they prescribed each of 300 participants one of four diets with varying levels of fat, protein, and carbohydrates and measured their food cravings and food intake. When participants began to eat less of a certain food, they craved it less.
The researchers say that to reduce cravings, people should simply eat the desired food less often, perhaps because our memories of those foods fade over time.
Overall, scientists agree that more research is needed to define and understand cravings and develop ways to overcome the conditioned responses associated with unhealthy foods. Meanwhile, there are several mechanisms that suggest that the healthier our diet, the healthier our cravings.