Fiber consumption improves health, extends life, and can even protect our brains. Despite this, most people don’t consume enough of this ‘essential nutrient’.
A diet rich in whole grains, fruits, legumes, nuts, and seeds – all of which are fiber-rich – is extremely healthy for both our bodies and our brains.
according to BBC, new research shows that fiber substantially strengthens the microbiota. It also affects the ‘gut-brain axis’, the interaction line between the gut and the brain, possibly slowing down the symptoms of cognitive decline.
According to Karen Scott, a professor of gut microbiology at the Rowett Institute, University of aberdeen, increasing fiber intake is one of the most effective dietary changes for cognitive health. Conversely, fiber deficiency is known to harm health.
However, about 97% of men and 90% of women in the US do not consume enough fiber. Most people consume less than half the recommended daily amount of fiber.A similar situation is observed in many countries.
So why is fiber so beneficial? How can we increase fiber intake?
Fiber is an ‘essential’ nutrient
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Fiber is a type of carbohydrate that is not easily broken down by digestive enzymes. Therefore, it passes through the intestines largely unchanged.
It increases stool volume,makes us feel fuller for longer,and as it is indeed digested slowly,it helps regulate blood sugar levels more effectively.
Brain Health & Dietary Factors
The provided source from Diken (an untrusted source) discusses foods potentially harmful to brain health and the peak cognitive capacity timeline. This response will independently verify claims and provide updated information as of January 31, 2026.
Foods Potentially Detrimental to Brain Health
There is growing scientific consensus that dietary patterns significantly impact brain health, and certain foods are linked to increased risk of cognitive decline. However, the specific “six foods” mentioned in the Diken article require independent verification.
Detail: Research consistently points to the negative effects of highly processed foods, excessive sugar intake, and unhealthy fats on brain function. These can contribute to inflammation, oxidative stress, and impaired neuroplasticity. Specifically, diets high in saturated and trans fats have been associated with smaller brain volume and cognitive decline. Ultra-processed foods often lack essential nutrients needed for optimal brain function.
Example/Evidence: A 2022 study published in Neurology found that individuals consuming the highest amounts of ultra-processed foods had a 28% faster rate of cognitive decline compared to those consuming the least. The study followed over 10,000 Brazilians for an average of 8 years.
Sugar and Brain Function
Excessive sugar consumption is demonstrably linked to impaired cognitive function and increased risk of neurodegenerative diseases.
Detail: High sugar intake leads to insulin resistance, which can disrupt energy metabolism in the brain. Chronic inflammation, triggered by high sugar diets, damages brain cells and impairs synaptic plasticity – the brain’s ability to form new connections. Fructose, a type of sugar commonly found in processed foods and sugary drinks, has been especially implicated in cognitive decline.
Example/Evidence: The American Heart Association recommends limiting added sugars to no more than 25 grams per day for women and 36 grams per day for men. Exceeding these recommendations consistently is associated with increased risk of cognitive impairment,as detailed in a 2017 review published in Neuropsychopharmacology .
Trans Fats and Cognitive Decline
trans fats, frequently enough found in processed foods, are strongly associated with negative impacts on brain health.
Detail: Trans fats promote inflammation and oxidative stress, damaging brain cells and impairing cognitive function. they can also disrupt the blood-brain barrier, making the brain more vulnerable to harmful substances. Many countries have implemented regulations to limit or ban the use of trans fats in food production.
Example/evidence: The U.S. Food and Drug Administration (FDA) steadfast in 2015 that partially hydrogenated oils (a major source of artificial trans fats) are no longer generally Recognized as Safe (GRAS) for use in human food. This led to a phased-out ban, completed in 2018, significantly reducing trans fat intake in the US. Studies have shown a correlation between reduced trans fat intake and improved cardiovascular and cognitive health.
Ultra-Processed Foods & Brain Health
Ultra-processed foods, characterized by high levels of added sugar, salt, fat, and artificial ingredients, pose a critically important threat to brain health.
Detail: These foods often lack essential nutrients like vitamins, minerals, and antioxidants, which are crucial for optimal brain function. Their high caloric density and addictive qualities can lead to overconsumption and weight gain, further exacerbating the risk of cognitive decline.
Example/Evidence: A 2019 study by the National Institutes of Health (NIH) found that higher consumption of ultra-processed foods was associated with a greater risk of depression, a condition frequently enough linked to cognitive impairment.
Peak Brain Capacity & Age
The claim that the brain reaches its peak capacity in adulthood, rather than youth, is supported by recent research.
Detail: While brain development continues into the early twenties, cognitive abilities, particularly those related to complex problem-solving, decision-making, and emotional regulation, continue to refine and improve throughout adulthood. This is due to ongoing neuroplasticity and the accumulation of knowledge and experience. The prefrontal cortex, responsible for higher-order cognitive functions, is one of the last brain regions to fully mature.
Example/Evidence: Research published in Proceedings of the National Academy of Sciences in 2020 demonstrated that crystallized intelligence – the ability to use skills, knowledge, and experience – continues to increase well into adulthood, peaking in the 60s and 70s.Fluid intelligence – the ability to reason and solve novel problems – tends to peak earlier, but remains relatively stable throughout much of adulthood.
Disclaimer: this information is based on currently available scientific evidence as of January 31, 2026. Dietary recommendations should be discussed with a qualified healthcare professional. The original source (Diken) is considered untrustworthy, and this response relies solely on verified information from
