A case study by Rebecca Finn, holistic children’s nutritionist and founder of Inner Bliss Kids.

Depression among teenagers is a significant and growing concern globally. Recent data indicates that over one in five children and adolescents worldwide experience a depressive episode or have depressive symptoms, and this prevalence is increasing. While there are many contributing factors to the onset of depression in teens, simple dietary and lifestyle shifts and targeting the gut-brain axis can enhance the body’s innate healing ability and have a significant positive impact on moods and long-term mental health outcomes.

This case highlights how building strength “from the inside out” through nourishing food, regular movement, quality sleep and a balanced gut microbiome can support teens in overcoming depression. These lifestyle and biological factors are deeply interconnected and influence mental health through multiple physiological and psychological pathways reducing inflammation, supporting brain function and neurotransmitter production, and helping regulate the HPA axis improving stress resilience.

Initial Consultation

A 13-year-old teenage boy presented with recently diagnosed depression. Multiple school-based and family stressors over the preceding 6-18 months, further compounded by the onset of puberty and associated hormonal changes, led to his mental health symptoms and a complete social withdrawal from peers and family members.

He had reluctantly started seeing a counsellor when he came to see me. His parents were concerned about his long-term mental health outcomes due to family history of anxiety and depression and wanted to explore non-pharmacologic strategies for supporting his mental health and overall wellbeing. He had also just been prescribed an antidepressant (10mg Lexapro).

Key presenting symptoms:

• Low moods – 1/10
• Low motivation
• Difficulty concentrating and making decisions
• Heightened anxiety and aggressive outbursts
• School avoidance
• Poor sleep habits
• Excessive screen time
• Cravings for processed foods, sweets, and soft drinks
• Limited fruit and vegetable intake
• No physical activity
• Chronic constipation
• Recent weight loss
• Social withdrawal

Prescription:

• Multivitamin and mineral tablet: 1 tablet daily with food; containing activated B’s, zinc, manganese, chromium, selenium, iodine, vitamin C, vitamin D, vitamin E and Grapeseed for healthy mood balance and nervous system function
• Curcuma longa (Turmeric) tablets: 1 twice daily; containing equivalent curcuminoids 100mg, to reduce neuroinflammation
• Comprehensive Gut Microbiome Testing

Diet & lifestyle advice:

• Anti-inflammatory diet prioritising nutrient-dense wholegrains, lean proteins, nuts, seeds, healthy fats, fruits, and vegetables
• Gradually reduce processed foods, sweets and soft drinks and replace with more nutrient-dense options
• Increase consumption of fibre-rich foods
• 10-minute daily walk around the block with his pet dog
• Minimum 9-10 hours sleep per night

Note: Dietary and lifestyle changes and supplementation were introduced very gradually to avoid overwhelming him as he had a history of being resistant to change.

Follow-up Consultation - 4 weeks

After implementing the suggested dietary and lifestyle changes, along with the initial prescription, the young boy’s parents noticed improvements in his appetite, moods (now 5/10) and bowel movements. They also felt that the Lexapro was starting to work and he was spending less time in his room and sleeping better. There were still some aggressive outbursts, a general lack of motivation, school avoidance and poor dietary choices.

The Gut Microbiome Test results showed very low levels of beneficial bacteria, high levels of bacterial overgrowth, two parasitic infections, moderate levels of inflammation, fat malabsorption and low secretory IgA.

The treatment was altered to focus on supporting his gut-brain axis and nutrient absorption.

Prescription:

• Antimicrobial capsule: 1 capsule twice daily with meals; containing Carum carvi (Caraway) Oil 100 mg, Punica granatum (Pomegranate) 283 mg, Allium sativum (Garlic) 50 mg, and Nigella sativa (Black Seed) 100 mg, to reduce bacterial overgrowth and parasitic infections
• Digestive enzyme capsule: 1 capsule twice daily before breakfast and dinner; containing Amylase, Protease, Glucoamylase, Lactase, Cellulase, Invertase, and Lipase, to improve protein and fat absorption
• Partially Hydrolysed Guar Gum (PHGG):  1 ½ tsp in smoothie daily, to promote growth of beneficial bacteria and support bowel movement regularity
• Multi-strain probiotic: 1 capsule twice daily, to improve beneficial bacteria levels
• Continued Multivitamin and mineral tablet
• Mum continued to ‘swap out’ nutrient-poor snack options at home for more nutrient-dense ones like grab-and-go veggie sticks with dip, nuts, oat bars, natural popcorn, protein smoothies, homemade biscuits, and muffins.
• Worked collaboratively with his parents to establish a Weekly Wellbeing Plan where he had to “earn” screen time (gaming) by doing daily exercise/movement, getting adequate sleep, gradually increasing attendance at school, contributing to household chores and spending some time with family and friends.

Follow-up Consultation - 8 weeks

His moods were now 8/10, he was going to sleep earlier and getting up easier in the mornings. Was back at school for half days and aggressive outbursts had reduced by 80%. Mum mentioned that he was starting to make better food choices and understand the connection between what he ate and how he felt. He had also gained weight and was looking much brighter and healthier.

His prescription was continued with no changes.

Follow-up Consultation - 16 weeks

Moods and motivation continued to improve. He was engaging more with his family and friends. Back at school doing full days. The school and counsellor both commented on his ‘remarkable progress.’ Medically assessed as no longer having ‘depression.’

His prescription was adjusted accordingly:

• Multivitamin and mineral tablet: 1 tablet daily with food
• Multistrain probiotic: 1 capsule daily
• PHGG: 1-2 tsp 3 times per week

Clinical Reflections

Depression can be a complex condition to treat. However, significant improvements can be seen with simple dietary and lifestyle shifts alongside targeting the gut-brain axis. Building internal capacity through nutrition, movement, quality sleep and gut health can create a synergistic effect on mood, energy and resilience complementing traditional therapies and medication, to overcome teen depression and improve long-term mental health outcomes.