AUTHORITY NUTRITION

Do Nutrient Deficiencies Cause Cravings?

Written by Alina Petre, MS, RD on May 20, 2017

Cravings are defined as intense, urgent or abnormal desires or longings.

Not only are they very common, but they're also arguably one of the most intense feelings you can experience when it comes to food.

Some believe that cravings are caused by nutrient deficiencies and view them as the body's way to correct them.

Yet others insist that, unlike hunger, cravings are largely about what your brain wants, rather than what your body actually needs.

This article explores whether specific nutrient deficiencies cause food cravings.

A growing number of people believe that food cravings are the body's subconscious way of filling a nutritional need.

They assume that when the body lacks a specific nutrient, it naturally craves foods that are rich in that nutrient.

For instance, chocolate cravings are often blamed on low magnesium levels, whereas cravings for meat or cheese are often seen as a sign of low iron or calcium levels.

Fulfilling your cravings is believed to help your body meet its nutrient needs and correct the nutrient deficiency.

Summary: Some people believe that cravings are your body's way of increasing the intake of certain nutrients that may be lacking from your diet.

In some cases, cravings may reflect an insufficient intake of certain nutrients.

Pica

One particular example is pica, a condition in which a person craves non-nutritive substances, such as ice, dirt, soil, laundry or cornstarch, among others.

Pica is most common in pregnant women and children, and its exact cause is currently unknown. However, nutrient deficiencies are thought to play a role (1, 2).

Studies observe that individuals with symptoms of pica often have low iron, zinc or calcium levels. What's more, supplementing with the lacking nutrients seems to stop the pica behavior in some instances (3, 4, 5, 6).

That said, studies also report cases of pica not linked to nutrient deficiencies, as well as others in which supplementation did not stop the pica behavior. Thus, researchers cannot definitively say that nutrient deficiencies cause pica-related cravings (6).

Sodium Deficiency

Sodium plays a critical role in maintaining the body's fluid balance and is necessary for survival.

For this reason, cravings for high-sodium, salty foods are often thought to mean that the body requires more sodium.

In fact, individuals deficient in sodium often report strong cravings for salty foods.

Similarly, people whose blood sodium levels have been purposefully lowered, either through diuretics (water pills) or exercise, also generally report an increased preference for salty foods or drinks (7, 8, 9).

Thus, in some cases, salt cravings can be caused by sodium deficiencies or low blood sodium levels.

However, it's important to keep in mind that sodium deficiencies are quite rare. In fact, excess sodium intakes are more common than insufficient intakes, especially in developed parts of the world.

So simply craving salty foods may not necessarily mean that you're sodium deficient.

There's also evidence that regularly consuming high-sodium foods can lead you to develop a preference for salty foods. This can create salt cravings in cases where extra sodium intake is unnecessary and even harmful to your health (7, 8).

Summary: Cravings for salty foods and non-nutritive substances like ice and clay may be caused by nutrient deficiencies. However, this is not always the case, and more research is needed before strong conclusions can be made.

Cravings have been anecdotally linked to nutrient deficiencies for quite some time.

However, when looking at the evidence, several arguments can be made against this "nutrient deficiency" theory. The following arguments are the most compelling.

Cravings Are Gender Specific

According to research, a person's cravings and their frequency are partly influenced by gender.

For example, women seem to be up to twice as likely to experience food cravings as men (9, 10, 11).

Women are also more likely to crave sweet foods, such as chocolate, whereas men are more likely to crave savory foods (11, 12, 13).

Those who believe that nutrient deficiencies cause cravings often propose that chocolate cravings result from a magnesium deficiency, while savory foods are often linked to insufficient intakes of sodium or protein.

However, there is little evidence to support gender differences in the risk of deficiency for any of these nutrients.

One study reports that men generally meet 66–84% of their recommended daily intake (RDI) for magnesium, while women meet around 63–80% of their RDI (14).

Moreover, there's little evidence to support that men are more likely deficient in either sodium or protein than women. In fact, deficiencies in either of these nutrients are very rare in developed parts of the world.

Limited Link Between Cravings and Nutrient Needs

The assumption behind the "nutrient deficiency" theory is that those with low intakes of certain nutrients are more likely to crave foods containing those nutrients (15).

However, there is evidence that this is not always the case.

One example is pregnancy, during which the baby's development can double requirements of certain nutrients.

The "nutrient deficiency" hypothesis would predict that pregnant women would crave nutrient-rich foods, especially during the later stages of the baby's development when nutrient needs are highest.

Yet, studies report that women tend to crave high-carb, high-fat and fast foods during pregnancy, rather than nutrient-rich alternatives (16).

What's more, food cravings tend to emerge during the first half of pregnancy, which makes it unlikely that they are caused by an increased caloric need (17).

Weight loss studies provide additional arguments against the "nutrient deficiency" theory.

In one weight loss study, participants following a low-carb diet for two years reported much lower cravings for carb-rich foods than those following a low-fat diet.

Similarly, participants put on low-fat diets during the same period reported fewer cravings for high-fat foods (18).

In another study, very low-calorie liquid diets decreased the frequency of cravings overall (19).

If cravings were truly caused by a low intake of certain nutrients, the opposite effect would be expected.

Specific and Nutrient-Poor Food Cravings

Cravings are generally very specific and often not satisfied by eating anything other than the craved food.

However, most people tend to crave high-carb, high-fat foods, rather than nutritious whole foods (20).

Consequently, the craved foods are often not the best source of the nutrient commonly associated with the craving.

For instance, cheese cravings are often viewed as the body's way to compensate for an insufficient calcium intake.

However, craving foods like tofu would be more likely to correct a calcium deficiency, since it offers up to twice as much calcium per 1-ounce (28-gram) portion (21).

Moreover, it could be argued that people with nutrient deficiencies would benefit from craving a wider variety of foods containing the required nutrient, rather than a single source.

For instance, it'd be more effective for those deficient in magnesium to also crave magnesium-rich nuts and beans, rather than chocolate alone (22, 23, 24).

Summary: The arguments above provide science-based evidence that nutrient deficiencies are often not the main cause of cravings.

Cravings are likely caused by factors other than nutrient deficiencies.

They can be explained by the following physical, psychological and social motives:

  • Suppressed thoughts: Viewing certain foods as "forbidden" or actively trying to suppress your desire to eat them often intensifies cravings for them (25, 26).
  • Context associations: In some cases, the brain associates eating a food with a certain context, such as eating popcorn during a movie. This can create a craving for that specific food the next time the same context appears (26, 27).
  • Specific mood: Food cravings may be triggered by specific moods. One example is "comfort foods," which are often craved when wanting to get over a negative mood (28).
  • High stress levels: Stressed individuals often report experiencing more cravings than non-stressed individuals (29).
  • Insufficient sleep: Getting too little sleep may disrupt hormone levels, which may increase the likelihood of cravings (30, 31).
  • Poor hydration: Drinking too little water or other liquids can promote hunger and cravings in some people (32).
  • Insufficient protein or fiber: Protein and fiber help you feel full. Eating too little of either may increase hunger and cravings (33, 34, 35).
Summary: Cravings can be caused by a variety of physical, psychological or social cues that have nothing to do with nutrient deficiencies.

Individuals frequently experiencing cravings may want to try the following strategies to reduce them.

For starters, skipping meals and not drinking enough water may lead to hunger and cravings.

Thus, consuming regular, nutritious meals and staying well-hydrated may decrease the likelihood of cravings (32, 36).

Also, getting sufficient amounts of sleep and regularly engaging in stress-relieving activities like yoga or meditation can help reduce the likelihood of cravings (29, 30).

In the event that a craving does appear, it could be useful to try identifying its trigger.

For example, if you tend to crave foods as a way to get over a negative mood, try to find an activity that provides the same mood-boosting feeling as the food.

Or if you're used to turning to cookies when bored, try partaking in an activity other than eating to reduce your boredom. Calling a friend or reading a book are some examples, but find what works for you.

If a craving persists despite your efforts to eliminate it, acknowledge it and indulge in it mindfully.

Enjoying the food you crave while focusing all your senses on the tasting experience may help you satisfy your craving with a smaller amount of food.

Finally, a proportion of people who experience consistent cravings for certain foods may actually suffer from food addiction.

Food addiction is a condition in which people's brains react to certain foods in a way that's similar to the brains of those who are addicted to drugs (37).

Those suspecting that their cravings are caused by food addiction should seek help and find potential treatment options.

For more, this article lists 11 ways to stop and prevent cravings.

Summary: The tips above are meant to help reduce cravings and help you deal with them if they do appear.

Cravings are often believed to be the body's way to maintain nutrient balance.

While nutrient deficiencies may be the cause of certain cravings, this is only true in the minority of cases.

Generally speaking, cravings are more likely caused by various external factors that have nothing to do with your body calling for specific nutrients.

An evidence-based nutrition article from our experts at Authority Nutrition.

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