It’s not hard to see that your diet affects your physical health. But research also tells us the saying “you are what you eat” applies to your mental health, as well. The link between mood, mental health, and food is actually so significant that many professionals now use the term “nutritional psychiatry” as a way to guide research and change treatment approaches.1 While dietary interventions are usually not enough on their own to manage a mental health condition, almost no individualized treatment plan would be complete without at least some assessment of the food choices a person makes.
A good quality diet along with other lifestyle interventions is increasingly shown to be an effective tool to help prevent and treat mental health disorders, as well as augment and optimize other aspects of care, like medications and cognitive behavioral therapy.1,2 As for a low-quality diet – nutrient-poor, calorically dense, and highly-processed – the repercussions can be serious.
How Your Food Choices Affect Your Brain, Mood, and Cognition
Eating minimally processed whole foods including fruits, vegetables, whole grains, healthy fats, and lean meats will help you get a better handle on your mental health – hands down. Here are a few reasons why:
Your brain needs a sufficient supply of nutrients to function properly.
Just like the rest of your body, brain and nervous tissue need raw materials from the food you eat in order to grow, repair, and perform its typical duties. This is why being deficient in certain vitamins, minerals, and antioxidants can increase the risk of certain mental health issues including psychosis and memory problems.2 Hydration matters too: even mild dehydration can impair cognitive function, especially in people with dementia.3,4
Not eating enough can worsen your mood.
One of the main effects of having low blood sugar (which can occur if you’re not eating enough food) is anxiety, irritability, and nervousness.5 These feelings often co-occur with telltale physical symptoms like a rapid heartbeat and dizziness, which many people associate with panic attacks.
Starvation is also stressful on the body, so when you go without eating for too long you may become more likely to consume (or even over-consume) processed foods whenever you do decide to eat. Why? Because these foods tend to be calorically dense and fast-digesting, not to mention high in fat, sugar, and salt—all of which are known to trigger the brain’s dopamine-based reward system (the same system triggered by certain drugs). Unfortunately, this makes you more likely to continue the addiction-like cycle of reaching for junk food whenever you’re stressed.6
Your food choices affect your gut, which impacts brain health and function.
Ever wonder why feeling nervous, sad, anxious, or other strong emotions can trigger gastrointestinal symptoms like upset stomach, “butterflies,” or even diarrhea? This is because your gut and brain are connected by an important nerve called the vagus nerve, creating the so-called “brain-gut axis.”7,8 Research shows that because of this “brain-gut” axis, your gut can literally affect brain function.
One recent study published in Nature Microbiology found that people with depression were missing two important types of bacteria in their gut. The authors interpreted their findings as evidence for a correlation between the diversity of a person’s gut bacteria with their mood and mental well-being.7,9 Meanwhile, we know that a poor diet rich in things like processed foods and alcohol can damage the friendly bacteria in the gut as well as the gut wall itself—which impairs the absorption of nutrients that your brain needs to function properly
Certain foods promote inflammation and can cause damage to the brain.
Refined sugar, trans fat, and other types of foods are known to drive inflammation throughout the body and brain. Excessive inflammation is harmful to cells and tissues and leads to mitochondrial DNA damage that accelerates aging and increases the risk of certain health problems.10 Incredibly, many disorders affecting the brain, including Alzheimer’s disease, depression, and schizophrenia, are correlated with increased inflammation.11,12,13
Various levels of evidence show beneficial effects of specific dietary interventions on mood and mental health conditions.
The current research available on nutritional interventions isn’t all complete nor equally strong. More studies need to be done to clarify exactly how food and dietary patterns can impact and modulate a person’s mental function. But there are several well-known correlations and clues that provide hope and dietary direction:
- Systematic reviews of the literature find that diets rich in whole grains, lean protein, healthy fat, and fresh fruits and vegetables (like the Mediterranean diet) can boost a person’s mood, promote happiness, and even reduce symptoms of depression.2,14
- The ketogenic (keto) diet may be all the rage now, but the low carb, high-fat diet has actually been around since the 1920s. It was first used as a way to help children with treatment-resistant epilepsy and has proven effective for reducing the frequency of epileptic seizures.2,15
- Studies, including at least one randomized controlled trial published PLOS One, show that providing children with folic acid (Vitamin B9) and Vitamin B12 supplements improves their problem-solving skills.16 Folic acid is also well-known as an essential nutrient for pregnant women since children born to mothers who are deficient in this vitamin are more likely to develop mental problems, neural tube defects, and even depression later in life.2
Alcohol and Drug Abuse
Good mental and emotional health provides people with a sense of peacefulness and greater control over their lives. It can help them gain a greater sense of resiliency and strength, which is essential for negotiating the normal stresses and challenges of daily life. Without good mental and physical well-being, we often see the development or worsening of behavioral and mental health conditions, including substance use disorders.
Alcohol and drug abuse cause severe nutritional deficiencies because the presence of these substances changes the body’s absorption ability to vitamins and nutrients. Furthermore, addiction often leads to poor dietary habits. While sometimes being under the influence, might cause a person to forget to eat, other times intense substance-induced cravings for sugary foods or drinks might become a common occurrence.
Over time the signs and symptoms of poor nutrition due to alcohol and drug abuse become more evident. Fatigue is a prevalent symptom, which worsens with deficiency of protein, iron, potassium, magnesium, Vitamins B, C, and D in the body. The lack of these vitamins and nutrient can contribute to the occurrence of dangerous health conditions, including:
- Cardiac failure
- Restless Leg Syndrome (RLS)
- Chronic Fatigue Syndrome (CFS)
There are also physiological symptoms, directly linked to poor diet that is often confused with withdrawal, allergies, or other common reactions.
Diarrhea and Constipation
Gastrointestinal function is directly affected by alcohol and opioid use, while bad nutritional habits tend to worsen these conditions. Persistent diarrhea can be a sign of lack of Vitamin B3, which can lead to irritable bowel syndrome (IBS). Unlike constipation, which can be a consequence of fiber, folate, magnesium, folate, and, most importantly, an adequate quantity of water. It is essential to remember that dehydration and bowel obstruction can cause severe risk to someone’s health, including death.
Neurobiological symptoms are often directly related to brain response and possibly caused by poor diet and nutrition. Especially when there are not sufficient vitamins such as B1, B3, B6, B12, and E. Also folate, amino acids, and Riboflavin are crucial to the proper function of the nervous system. When these necessary vitamins and nutrients are missing, people may feel:
- Loss of balance
- Muscle pain and spasm
- Peripheral neuropathy
- Numbness and tingling of extremities
- Restless legs
- Feelings of numbing and vibration in some regions of the body
It is crucial to address the existing diet and nutritional deficiencies when trying to recover from alcohol and drug abuse. Proper nutrition can significantly reduce the discomforts of withdrawal and the intensity of cravings.