How Alcohol Affects Your Nutrition—and Your Mental Health

Most people know alcohol has calories. Fewer realize that alcohol fundamentally disrupts how your body absorbs and uses nutrients—and that these nutritional deficits directly affect your brain, mood, and mental health. As a psychiatry practice in Lilburn, Georgia, we see this connection regularly.

The Empty Calorie Problem

Alcohol packs 7 calories per gram—nearly as calorie-dense as fat—with zero nutritional value. A moderate evening of 3-4 drinks adds 400-800 calories with no protein, vitamins, minerals, or fiber. Worse, your body prioritizes metabolizing alcohol above everything else, meaning fat burning essentially stops until the alcohol is processed. Food consumed alongside alcohol is more likely to be stored as fat.

How Alcohol Depletes Your Vitamins

B Vitamins

Alcohol significantly depletes B1 (thiamine), B6, B12, and folate by damaging the stomach lining, increasing urinary excretion, and impairing liver storage. B vitamins are critical for energy production, cognitive function, and mood regulation. Deficiency contributes to fatigue, brain fog, irritability, and depression—symptoms that often bring patients to our office.

Magnesium and Zinc

Alcohol increases excretion of both minerals. Magnesium deficiency contributes to anxiety, muscle tension, and poor sleep. Zinc deficiency affects immune function and mood. Many people who stop drinking notice improvements in anxiety and sleep quality as these mineral levels normalize.

Vitamin D

Alcohol impairs the liver's ability to convert vitamin D to its active form. Given that many people in the Southeast are already vitamin D deficient, adding alcohol to the equation compounds the problem—affecting bone health, immune function, and mood.

Blood Sugar Disruption

Alcohol interferes with blood sugar regulation, causing spikes and crashes that affect energy, mood, and cravings. This rollercoaster can mimic or worsen symptoms of anxiety and depression, making accurate psychiatric diagnosis more challenging when a patient is actively drinking.

The Nutrition-Mental Health Connection

Your brain is the most metabolically demanding organ in your body. When alcohol depletes the nutrients your brain needs—B vitamins for neurotransmitter production, magnesium for nervous system regulation, zinc for cognitive function—mental health suffers directly.

This is why patients who reduce their alcohol intake often notice mental health improvements even before psychiatric treatment begins. The brain is simply getting more of what it needs.

What Recovery Looks Like

Within weeks of reducing or stopping alcohol, most people experience:

• Improved energy as B vitamin levels recover
• Better sleep as magnesium levels normalize
• More stable mood and reduced anxiety
• Clearer thinking and improved focus
• Healthier appetite and reduced sugar cravings