Thembelihle Zwane
19 August 2025
In today’s fast-paced world, junk food has become a convenient go-to for millions. Burgers, fries, sugary snacks, and fizzy drinks offer quick satisfaction and comfort. But beyond the immediate gratification lies a less visible, yet profound impact: the toll that junk food takes on our mental health.
Junk food is typically high in refined sugars, unhealthy fats, and artificial additives—ingredients that can disrupt brain chemistry. Nutritionist Dr. Thandi Mthembu explains, “The brain relies on a steady supply of nutrients to function optimally. Diets high in processed foods lead to inflammation and oxidative stress, which can impair cognitive function and mood regulation.”
Research increasingly links poor diet with conditions such as depression, anxiety, and even cognitive decline. Registered dietician Sipho Nkosi adds, “Consuming excessive junk food can cause blood sugar spikes and crashes, which affect energy levels and emotional stability. Over time, this can exacerbate feelings of irritability, fatigue, and low mood.”
Psychiatrist Dr. Lindiwe Zulu highlights the importance of gut health in mental well-being. “Our gut microbiome communicates directly with the brain through the gut-brain axis. Junk food negatively alters this balance, reducing beneficial bacteria and increasing harmful ones, which can influence neurotransmitter production linked to mood and anxiety.”
This means that what we eat doesn’t just feed our bodies—it shapes our emotions and thought patterns. Eating nutrient-poor junk food starves the brain of the vitamins and minerals it needs to produce serotonin, dopamine, and other mood-regulating chemicals.
The challenge, as nutritionist Dr. Mthembu notes, is that junk food can also be addictive. “The combination of sugar, fat, and salt triggers the brain’s reward centres, creating cravings and habitual consumption that are difficult to break.” This cycle not only harms physical health but also traps people in a loop of emotional eating, often worsening anxiety and depression.
Experts agree that improving mental health starts with what’s on our plates. Dietician Nkosi encourages incorporating whole foods rich in omega-3 fatty acids, antioxidants, and fibre—like leafy greens, nuts, seeds, and fatty fish. “These foods support brain plasticity and reduce inflammation, helping to stabilise mood and enhance cognitive function.”
Psychiatrist Zulu advocates for a holistic approach that combines nutrition with therapy and lifestyle changes. “Food is one piece of the puzzle. Regular exercise, adequate sleep, and social connection are critical for mental well-being.”
Practical Tips to Reclaim Your Mental Health from Junk Food
- Plan Meals Ahead: Preparing balanced meals reduces reliance on fast food.
- Stay Hydrated: Sometimes cravings mask dehydration. Drink water regularly.
- Mindful Snacking: Choose nutritious snacks like fruits, nuts, or yoghurt instead of chips or sweets.
- Limit Sugary Beverages: Replace sodas with herbal teas or infused water.
- Seek Support: If emotional eating is a concern, consult a nutritionist or mental health professional.
While junk food might offer momentary comfort, its hidden costs on mental health are too significant to ignore. By understanding the powerful connection between diet and mind, we can begin making choices that nourish both body and soul—fuelling a happier, healthier life from the inside out.
