Finals week: the dreaded seven or so days for all college and university students. It’s the time of year when all that matters are grades, grades and more grades. A common mistake many make during this crucial period is to eat poorly and unhealthily. Junk food, lots of chocolate, energy drinks and crisps are often eaten in place of normal meals to “keep energy levels up”. However, this is not only harmful to your long-term health, but can also negatively affect your exam performance. Here are some brain food suggestions to ensure you're at your best on exam day. Oily fish via GIPHY Salmon, sardines and mackerel are among the healthiest types of fish, as they contain lots of protein and omega 3, which is essential to keeping a functioning brain working well. Herring and trout are other possible options, but the simplest (and cheapest) meal for students is probably sardines on toast. Choose whole-wheat bread and you'll have a healthy, long-lasting meal, combining complex carbohydrates, vitamins and protein. Eggs via GIPHY Let's face it: eggs are one of the most versatile foods on Earth. Fried, boiled or poached, eggs are healthy and good brain food. They're a great way to start the day, and are more likely to leave you feeling full than sugary cereals or pastries. Just one egg contains vital nutrients, 6g of protein, vitamin B12 (which helps convert glucose into energy) and less than 100 calories - depending on how you cook it. Dark leafy greens via GIPHY Kale, chard, spinach, broccoli: the list of healthy dark leafy greens is a long one, and they're a vital source of vitamins in the run-up to exams. All dark greens are packed with vitamin K, which helps build pathways in the brain, as well as naturally occurring nitrates and antioxidants. You'll also get a healthy amount of B6 and B12 from some of these vegetables, which are associated with improvements in alertness and memory. Peanut butter via GIPHY Go on, eat it out of the jar with a spoon. We won't judge you. Many people think peanut butter is an unhealthy food, but it actually contains healthy fats and lots of protein per serving. This means that as a brain food, just a little can keep you full for a long time. If you'd rather have porridge in the morning instead of eggs, try mixing some peanut butter into your morning bowl, a delicious way to start the day. Nuts, in general, are also an extremely good brain food, so stock up on snacking packs before your next trip to the library. Green tea via GIPHY Caffeine, in the short-term, can provide a useful boost immediately before an exam, but don't be tempted by stomach-churning energy drinks. Coffee is a good alternative, but should be drank with caution. Drinking too much could leave you unable to focus properly, while becoming dependent upon it will only make you more fatigued in the long-run. Green tea is a good alternative to high-caffeine options, as it provides antioxidants as well as boosting your concentration. Fresh fruit via GIPHY If you need a sugar boost, the naturally occuring sugars in fresh fruit are going to be much more useful than a chocolate bar or two. Darker coloured fruits, such as blueberries, are thought to contain more antioxidants, but you'll feel the benefits of eating any fruit, whether it's a banana, an orange or even a slice of melon. This article was originally written in March 2013 and was updated in April 2017 Source