Is Junk Food Shrinking Your Brain?

junk food

We often identify intelligent people as ’big brained’ individuals – which is something that is still being widely debated. Although the size of someone’s brain may not dictate their IQ, there are most certainly structures within the brain that need to be studied in greater detail, focusing on the relation between size and function.

See Also: Top 5 Foods to Boost Brain Power

Recently, it’s been uncovered that diet directly influences a specific region of the brain. We’ve long been told that diet will impact anything from energy levels to mood, but what effect does junk food have on brain structure? More specifically, what occurs in terms of functionality when the structure of one’s brain has been altered?

What the Research Has to Say

For the first time, it’s been reported that those who have an unhealthy diet, display a smaller part of the brain, which is critical for memory, learning, and overall mental health. Conducted at the Australian National University, it was found that subjects who consumed a poor diet exhibited smaller hippocampi and in contrast, those that ate a healthier diet exhibited larger hippocampi.

We’ve known for quite some time that junk food hinders your health – affecting your weight, mood, disease risk, and now we know that junk food also affects the size of our brain. This means that all those high-sugar snacks and processed foods are transforming the structure and possibly the functionality of your hippocampus.

The study, published in BMC Medicine, examined 250 participants who were in their early 60s in 2001. Based on dietary questionnaires, participants were categorized into one of two groups – those who consumed a Western diet consisting of processed food, salt, sugar, and fats; and those who consumed a prudent diet consisting of mainly fish, fruits, and vegetables.

Researchers took numerous potential contributing factors into account, including gender, mental health, and medication – yet a poor diet was still considered to be a strong predictor of hippocampus size. The effects of a poor diet on the hippocampus have been known for quite some time, however, prior to this research we had only seen these results with mice and rats. What do these findings mean?

Understanding the Hippocampus

Before we focus on what this new research truly means, it’s critical to understand the hippocampus itself. This small part of the brain sits around ear level and as mentioned above, plays a major role in emotion, memory, learning ability, and overall mental health.

It was only recently that a true connection was made between the structural and functional aspects of the hippocampi. More specifically, it’s been found that the shape of one’s hippocampus, may be a strong predictor regarding memory function. Of course, the size of this brain structure is also commonly taken into account.

What Does It All Mean?

Big Bang theory


Of course, there are some unknowns while focusing on mental health, cognitive functioning, and neurological factors. With that being said, plenty of research has examined this key area of the brain, especially in terms of diet and mood, as well as diet and cognition.

Plenty of previous studies have reported these effects on animals, mainly mice and rats. When diet negatively affects mood or cognitive ability – changes tend to be seen within the hippocampus. When consuming a diet that is high in fat and sugar, it appears that these foods negatively impact brain proteins, known as neurotrophins.

These proteins not only protect neurons, but also promote the growth of new neurons within the hippocampus itself. In comparison, when consuming foods that are rich in antioxidants and beneficial fats (like omega-3 fatty acids), there’s actually an increase in these proteins.

As a growing body of related research piles up, these recent findings are highly significant regarding public health. Although past research did not specifically report these recent findings, there has long been a list of recommended ’brain foods’ which have been said to potentially protect the public against degenerative conditions, such as Alzheimer’s and Parkinson’s.

This most recent Australian study simply confirmed that the foods which have been suggested in the past, do in fact have significant effects on brain structure. Yes, more research needs to be done regarding the exact cause and effect in terms of diet and brain function, however, it’s pretty clear that junk food alters the brain. So, which foods should you be consuming? How do they relate to your hippocampi and related functions?

1. Oily Fish

This is perhaps one of the most obvious and well-known brain foods, offering high concentrations of omega-3 fatty acids. These healthy fats are known to promote optimal nerve and brain function, especially regarding memory.

In 2014, a study was released which reported the positive effects of oily fish on brain size and nerve cells in the hippocampus. As we know, this is the brain’s memory center. It was reported then, that the enhanced neural volume correlated with omega-3 consumption could reduce brain aging effects by up to two years.

This impressive study ran for eight years, utilizing MRI scans to measure brain size. Participants with higher levels of fatty acids, experienced a hippocampus area that was nearly 3 percent larger. Of course, the same results had not yet been expressed regarding the opposite effect – in terms of junk food and a shrunken hippocampus.

2. Berries

Berries, specifically blueberries, strawberries, and elderberries – all offer high concentrations of flavonoids. In particular, quercetin, which reduces inflammation at a cellular level. This beneficial flavonoid also increases cellular activity and overall energy production.

Past research has shown that rats which are fed berry extracts, experience less neuronal damage as they age. In 2005, researchers began to see that berries offered more than anti-inflammatory and antioxidant benefits. It was found that blueberries improved neural plasticity within the hippocampus.

When the brain is more plastic and flexible, this typically indicates positive health. You can obtain a range of beneficial flavonoids from other sources as well, such as citrus fruits, dark chocolate, and red wine. Remember, if you’re going to consume alcohol, do so in moderation. No more than one glass of red wine daily for women and two glasses daily for men.

3. Turmeric

Cooking with turmeric, consuming turmeric milk, or simply blending this spice into your smoothies – are all great ways to protect your brain and boost immune function. When chronically stressed rats were given curcumin, the active ingredient in turmeric, increased hippocampal neurogenesis – the development of new neurons.

4. Dark Leafy Greens

Dark leafy greens, such as spinach, kale, and swiss chard, all help strengthen your hippocampus. Although dark leafy greens yield a wide range of beneficial nutrients, their high concentration of magnesium is what supports nerve and brain health. This mineral supports synapses, allowing neurons to communicate with one another. Once these connections diminish, this is what results in age-related cognitive decline.

In one study, published in the journal Neuron, it was found that a diet rich in magnesium, improved memory and learning. Rats who consumed more magnesium, were found to have an increased density of connections between neurons in the hippocampus. Whole grains, nuts, green vegetables, and seeds are all great sources of magnesium. Based on this recent study, it’s not just seniors who should be concerned with their brain’s synapse density.

See Also: Simplifying Your Life To Detoxify Your Brain

This recent research is both exciting and alarming, helping to guide us towards better choices. So, the next time you’re reaching for a burger, fries, and soda, remember this food for thought – what you choose to consume today, can potentially affect your mental health and memory later in life.