Whether your teen is buried in revision materials or still searching for the motivation to begin, what they eat — and when — genuinely matters. While many believe that long hours of study are the key to academic success, lifestyle habits during revision and exam periods are just as crucial.
The brain is a remarkable organ made largely of fat and water. It relies on key nutrients to function well but primarily uses glucose as its main fuel source. Readily available glucose supports motivation, concentration and sharpens focus. Despite its size, the brain uses around 20% of the body’s total energy intake, so keeping it well-fuelled is essential.
Regular meals and snacks help maintain a steady energy supply to support engagement, productivity and focus. Planning a meal or snack every 2–3 hours helps provide consistent fuel. To avoid sharp rises and dips in blood sugar, meals and snacks should include a slow‑releasing carbohydrate (ideally wholegrain), balanced with protein, healthy fats and fibre.
Although sugary snacks can be tempting for a quick boost, they often lead to an equally quick crash. Instead, choose foods like nuts, fruit, vegetables, cereal, eggs or cheese and crackers — all quick, simple and nourishing options.
Beyond Fuel: Other Key Nutritional Considerations
Hydration
Most of us know the general guidance of 6–8 glasses of water per day, though some people need more. Even mild dehydration can reduce mental and physical performance. It’s easy to miss thirst cues when deeply focused. Offering a variety of drinks can help maintain interest in drinking for teens to find this more difficult — water, milk, fruit teas, hot chocolate or small amounts of fruit juice (150–200ml per day).
Vitamins and Minerals
Iron, iodine, magnesium and zinc are just some of the nutrients the brain needs to function at its best.
- Iron Essential for transporting oxygen around the body, supporting energy and motivation. Rich sources include red meat (beef, lamb, pork), with smaller amounts in chicken, fish, dark leafy greens, beans, pulses, peas, nuts and seeds.
- Iodine Important for brain development, especially during the teenage years. Low iodine levels are linked with reduced academic performance. Good sources include fish, seafood, seaweed, potatoes and fruits such as cranberries and strawberries.
- Magnesium Vital for a healthy nervous system and basic cellular function. Include magnesium-rich foods throughout the day: leafy greens (e.g., spinach), wholegrains, meats (chicken, fish, beef), nuts and seeds (almonds, peanuts, cashews, pumpkin seeds).
- Zinc Essential for neurotransmission — the brain’s communication system — and plays a key role in learning and cognition. Found in lamb, beef, chicken and leafy greens.
- Vitamin D Supports brain development, learning and mood regulation. After winter, levels are often low in both adults and children who haven’t supplemented. A daily 10µg supplement can help restore levels. Vitamin D is produced through sunlight exposure and cannot be reliably obtained from food alone.
- Essential Fatty Acids (Omega‑3) Omega‑3 fats support brain health and function, and must come from the diet. Rich sources include oily fish (salmon, tuna steak, mackerel, sardines). Plant-based options include pumpkin, sunflower, chia and flaxseeds, walnuts and soya products.
- Dietary Fibre Fibre supports gut health and helps regulate energy levels. Aim for a mix of soluble fibre (fruit, vegetables) and insoluble fibre (wholegrains, nuts, seeds).
Top Tips
- Plan meals in advance to ensure key nutrients are included and to keep meals varied and interesting.
- Prepare snacks ahead of time to avoid relying on quick, highly processed options.
- Build snack breaks into the revision schedule.
- Treat mealtimes as intentional breaks from studying — they help reset the body, support mindful eating and prevent overeating.
- Offer a variety of drink options to encourage hydration.
- Try different serving styles — with or without a straw, or using sports‑style bottles — to suit your teen’s preferences and support emotional regulation by offering a calming sensation.
- Avoid caffeine-based drinks such as energy drinks or coffees; these cause a false sense of energy and can lead to disrupted sleep patterns and over stimulation, which can in turn inhibit learning.
- Encourage your teen to help prepare snacks or bake as a way to unwind away from the desk.