Eating for mental health: How a great diet can help you to feel better physically and mentally

Making sure that the body receives a balanced diet does more than just help keep you physically healthy. Emerging research suggests that proper nutrition also plays a role in good mental health.

In a world of processed food, it can be very difficult to keep track of exactly what we are eating – especially when living increasingly hectic lives. Specialist diets have for years suggested that cutting out specific ingredients, while including others holds the key to unlocking better health for all of us. This is fundamentally true for our mental health as much as for our physical health. With the rise of ultra-processed food products, it can be extremely difficult to know exactly what we consume on a regular basis – which means we can often make poor nutritional choices that adversely affect our health, all while never understanding why.

We have always known that having too much sugar in our diets is a bad thing, but it is only relatively recently that the truth about how bad it really is has clearly emerged. Studies – dating back to 2004 – have demonstrated that too much refined sugar can lead to a heightened risk of depression and schizophrenia – and that ensuring that we maintain a low-sugar diet is essential to helping keep the brain (and the rest of our bodies) functioning in a healthy manner. A follow-up study to the original research in 2017 – this time by researchers at University College London, confirmed the findings, noting that an overconsumption of sugar also leads to depression.

Chronic mental illnesses such as the types caused by an overconsumption of sugar have also been proven to shorten our lifespans, and to increase mortality rates. This is true of even minor mental illness – so taking the time to make sure that we eat properly is more important than ever if we want to see our brains stay healthy as we age. In order to do this, we need to ensure that our brains manufacture sufficient levels of the protein BDNF, which it uses to repair and power itself.

BDNF – or brain-derived neurotrophic factors – is the name given to the proteins produced by our brains to help regenerate and power themselves. The lower the levels of recorded BDNFs, the lower the levels of brain health, so keeping levels high by avoiding potential inhibitors (such as products with high levels of processed sugars) holds the key to long-term mental health benefits.

Low BDNF levels have been linked to a litany of mental disorders – from serious disorders like Alzheimer’s Disease, and epilepsy to anorexia and OCD, all of which are characterised by a lack of BDNF levels in the brain. Low BDNF has also been suggested to inhibit learning, meaning that school-age children also need to avoid an overconsumption of sugar in order to maximise their learning opportunities.

BDNF levels also drop markedly as we age – which is why cognitive decline is often observed in the elderly. Recent research now suggests that by reducing sugar (and swapping the sweetness for a healthier, natural source like stevia), brain performance can be maintained for longer as BDNF is conserved.

Beyond our mental health, evidence has emerged that an overconsumption of sugar can affect even our immune systems. Professor Robert Lustig, of the University of California, cites evidence that excessive levels of fructose – a common sweetener in processed foods – can increase insulin resistance. While the link between excess sugar and diabetes is by now well understood, the insulin resistance also correlates with wider issues regarding the functionality of leptin receptors – the system in our bodies directly related to making us feel satisfied after eating. This research, which was published in 2022, demonstrates that there is still a significant amount of damage caused by our overreliance on traditional sugar that we are yet to fully understand.

This suggests that by eating high-sugar foods, our bodies see a decreasing ability to recognise when we need to stop eating – causing continued intake of sugars, repeating the cycle, with increasingly serious effects each time, declining our ability to feel healthy in body or mind.

For those who are considering a switch to a more consciously healthy diet, cutting down on sugar should be the absolute priority. This change in fundamental food philosophy is being experienced not only by consumers looking to make better food choices, but also by manufacturers, who are looking to reduce their dependence on unsustainable refined sugar and move across to a more natural and healthy form of sweetness.

The unrivalled natural sweetness of stevia provides an opportunity to keep the same delicious flavours of all your guilty pleasures, while reformulating them to ensure that they are low or even zero-sugar products. This keeps BDNF levels in the brain high and helps to keep fat – another ingredient linked with BDNF reduction – lower than ever.

Given the evidence for the benefits of a low-sugar diet in children, adults and the elderly, there is clearly no better time to take control of what you eat, and choose a new kind of sweetness that reflects the healthier, more sustainable future that we are all searching for.