Metabolic Rewiring for an Aging Brain

We are all aware that brain health and mental wellness deserve more awareness.

When it comes to diet and lifestyle, most of the attention over the past 70 years has been on the heart. It’s understandable given the prevalence of cardiovascular disease. In comparison, it is only recently that the relationship between the health and metabolism of the brain has been considered unique. Whether it is due to the emergence of Type 3 Diabetes (insulin resistance of the brain), the exponential increase in neurodegenerative disorders, or the large number of Americans who suffer from depression, the spotlight has finally fallen on what the brain needs.

The brain’s metabolism is unique and what might work for the rest of the body doesn’t always support its function.

While the brain is a relatively small organ at approximately 2% of bodyweight, it demands over 20% of the body’s energy. That energy can’t simply come from anywhere either. Unlike other organs that can use a wide variety of fatty acids, the blood-brain barrier puts limits on these. This tightly regulated (hopefully) control of what can cross over leaves neurons with two main sources of energy: glucose and ketones.

Insulin resistance of the brain is becoming increasingly common.

If the brain develops insulin resistance (which can occur separately from the rest of the body) then the use of glucose as a fuel becomes hindered. Without a supply of ketones (which can only happen with at least some level of carbohydrate restriction), neurons suffer an energy shortage. Slowly, over time, the effects become apparent. Short-term memory loss, brain fog, and an eventual neurodegeneration that closely mirror Alzheimer’s disease. All of which are becoming increasingly common yet seldom tied to the brain’s unique metabolism.

On Campus

Rewire Your Brain

Metabolic secrets for healthy aging

November 20–22, 2026

Breaking carbohydrate dependency is the path to brain recovery for many individuals.

The key is to maintain brain metabolic flexibility. This can be achieved by providing an alternative fuel source. Moving away from glucose or sugar dependency towards a metabolism that includes ketones is arguably essential for optimal neurological aging. Producing ketones requires some combination of time restricted eating with a fat- and protein-based way of eating. Limiting carbohydrates to the small amounts found in select vegetables and avoiding the more carbohydrate-dense foods creates the perfect scenario. Even modest amounts of time with this approach offer the brain an opportunity to reset and recover. When we look at the composition of the brain, which is largely made up of fatty acids, cholesterol, and proteins, it makes sense.

The aging brain often needs an oil change.

The quality of the fats and oils has a great effect on the brain. It’s no mystery why populations that eat fish more regularly have a significantly lower risk of neurological disease and a less cognitive decline as they age. The brain has very specific fatty acid requirements and these are not limited to the omega 3 types that most people are aware of. There are others that play pivotal roles in the health of mitochondria and in the prevention of amyloid plaques. Two of these are types of saturated fat found only in certain species of fish and a handful of other foods. As much as these fatty acids are often missing in one’s diet, there are others that occur in abundance. Often exceeding the brain’s requirements and creating inflammation.

The blood-brain barrier is incredibly important as well. It requires maintenance and a supply of specific short chain fatty acids produced by gut bacteria. There’s a well understood role for the fermentation of soluble fiber in maintaining gut wall integrity. What’s less appreciated is the effect that one of those same by-products of fermentation has on the blood-brain barrier. N-butyrate, produced when specific families of bacteria help us digest certain parts of the plants we eat, acts as a signal to reinforce and tighten the blood-brain barrier. This prevents a variety of inflammatory molecules from leaking into sensitive brain tissue. In addition, n-butyrate can be described as a primary source of increased brain-derived-neurotropic factor (BDNF), often referred to as “Miracle-Gro for the brain” given its ability to foster new neural connections, learning, and memory, even in elderly populations.

Many of us have grown up with nutrition messaging centered on what to avoid but we’re now seeing that brain health starts with being nourished first.

Brain nourishment, and ultimately its health and function, requires a reliable source of energy and an array of nutrients. Nutrients that include vitamins and minerals from A to zinc, fatty acids found in certain foods, and fiber-gut microbe metabolites. All of these can be provided by eating the right combination of foods and ultimately giving new meaning to the words; Food for Thought.