Just as there are foods that boost neurological health, offer protection from dementia and improve memory, there are those capable of doing the opposite. Some major components of your diet could well be making your mind old before its time, predisposing you to cognitive problems in later life. Here’s what you need to know about six of the worst offenders, along with a few suggestions that will help you actively support your brain.
1. Trans fat
Often discussed in the context of weight gain and cardiovascular risk, trans fat has been shown to raise LDL (i.e. “bad”) cholesterol levels. It promotes arterial hardening, increases inflammation, and has an adverse influence on neuroplasticity—your brain’s ability to adapt in response to behavioral, environmental and psychological triggers. Alarmingly, a recent study in the journal Neurology revealed that trans fats actually shrink the brain in ways similar to those experienced by Alzheimer’s patients. Avoid products with “partially hydrogenated oils” on the ingredients list as well, as this term also indicates trans fat content. Doctors advise cutting trans fats out of your diet altogether.
Tuna offers plenty of health benefits, but it shouldn’t be a daily part of your diet due to the risk of mercury consumption it carries. According to scientists at the University of Florida, people who have the highest levels of mercury in their blood have a 5% reduction in overall cognitive function. Better alternatives are salmon and mackerel, both of which increase neurological health by providing you with plenty of omega-3 fatty acids but which typically contain only low levels of mercury.
3. Saturated fat
Unlike trans fat, it’s relatively safe to consume saturated fat in moderation. However, your intake should be no more than 4g per hour, like saturated fat lines your arteries and increases inflammation. Both of these bodily changes are associated with cognitive impairments (such as reduced memory) and may heighten your risk of developing vascular dementia. There are also short term consequences, as your ability to learn and memorize new information dips just ten minutes after consuming a meal or snack that’s high in saturated fat.
Although tofu is generally thought of as a portion of healthy food, it can actually age your brain if regularly consumed. For example, one large study performed in 2008 showed that participants who ate the most tofu had the poorest memory. This result was even more striking in those who were in their late 60s or older. It is thought that soy products containing high levels of phytoestrogens both lower memory function and increase the risk of degenerative neurological disorders.
5. Extra sugar
Neurological research shows that excessive sugar consumption can reduce cognitive function by triggering inflammation in the hippocampus—the area of the brain that processes and controls memory. There is also evidence that frequent blood sugar spikes can lead to neuronal and vascular damage in the brain. You may want to be especially conscious of added fructose in drinks and snacks, as tests on rats indicate that fructose consumption reduces navigation capabilities.
One plausible hypothesis is that fructose can inhibit a brain cell’s ability to store and use energy in ways that facilitate thinking and learning. However, don’t worry too much about the fructose in fruit—there is no compelling evidence that it causes mental decline when consumed in your favorite fresh snacks.
6. Extra salt
According to findings published in the journal Neurobiology of Aging, the proven link between high salt intake and poorer vascular health may also lead to more significant cognitive decline earlier in life. In this particular study, people who consumed the most salt were more likely to attain progressively lowering scores on tests of cognitive function over a three year period. As well as staying away from the temptation posed by the salt shaker, note that microwaveable meals and other processed meals are often surprisingly high in added salt.
Foods that support brain health
In addition to cutting back on the above foods, it’s wise to adapt your diet in a way that proactively enhances cognitive health. Here are some great examples of brain-supporting ingredients:
- Blueberries, which appear to slow the progression of Alzheimer’s disease and can improve memory, motor skills and learning capacity in older age.
- Cinnamon, which may reduce the inflammation associated with degenerative neurological disorders and which has been shown to improve symptoms in both Parkinson’s and Alzheimer’s sufferers.
- Apples and tomatoes, which contain chemicals (quercetin and lycopene respectively) that help to protect brain cells from toxic free radicals that may be linked to dementia risk.
- Pumpkin seeds, which give you an impressive amount of your daily recommended intake of zinc, thereby supporting your problem-solving skills and your memory.
- Walnuts, which can break down some of the dangerous brain plaques that are often seen in those who go on to develop Alzheimer’s.
- Oatmeal, which not only gives you a slow, steady release of energy but also immediately gives you a boost in short-term and spatial memory,