How Important Is Fat to the Brain Cells?
How Important Is Fat to the Brain Cells?
The brain is the single most expensive organ in the body concerning metabolic needs.
It occupies only 5 percent of our total mass but uses at least 20–30 percent of our body’s energy supply to meet its considerable demands.
Many people assume that the brain needs glucose for this energy, but few are aware that it prefers ketones, the energy unit of fat, for its dominant fuel source!
The brain can and does use glucose, especially when a person consumes a diet that is dominated by carbohydrates or during an emergency, but glucose isn’t as essential to the day-to-day functioning of the brain as is commonly presented and believed.
In the absence of carbohydrates, once metabolically adapted, the brain will readily and naturally turn to ketones as its primary source of fuel.
The brain uses ketones in a state of ketosis.
Cerebral ketone use is prevalent, for instance, in newborn infants nursing on fat-rich mother’s milk.
The switch to dependence on glucose does not occur until carbohydrates are introduced into a child’s diet.
The enzymes responsible for ketone metabolism, d-beta-hydroxybutyrate dehydrogenase, acetoacetate-succinyl-CoA transferase, and acetoacetyl-CoA thiolase, are present in brain tissue in sufficient amounts to convert ketones into acyl-CoA and to feed them into the tricarboxylic acid cycle at a sufficient rate to satisfy the metabolic demands of the brain (Siegel et al. 1999)
Cerebral use of ketones is increased more or less in direct proportion to the degree of ketosis.
The body preferentially burns excess sugar whenever it is present, mainly to rid the body of this damaging substance in any way it can.
Sugar or glucose will also dominate as a source of brain fuel when turbocharged energy is in sudden demand, such as in an emergency.
Sufficient carbohydrate stores in the form of glycogen in the liver are always available for this.
No one ever needs to consume carbohydrates for glucose to be available to the brain or body when needed.
Depending entirely on glucose as a primary fuel for the brain and body is
ultimately unnatural and problematic, in fact, but this is unfortunately the metabolic state in which the vast majority of people reside.
Brain cells don’t respond much to insulin and are therefore more vulnerable than just about any other tissue to the ravages of glycation and the oxidation or free-radical activity that glucose and glycation attract.
There is no such thing as a safe, low level of glucose.
Glucose and other sugars, such as fructose, always glycate and attract free-radical activity to some ongoing degree, no matter what.
Although we need glucose to some extent for feeding our red blood cells, glucose is really what eventually kills many of us a cruel irony.
We do maintain some control over the rate of glycation and degeneration, though, through what we choose to eat and what supplements we take.
Glycation is the primary cause of brain degeneration in aging and also in Alzheimer’s disease.
Alzheimer’s disease is basically a state of brain neuropathy.
Notice the sweet tooth in many patients with this condition.
Beta-amyloid proteins, or glycated tangles of proteins, clump and stick together in the brain and eventually cause the symptoms later identified as Alzheimer’s disease
The same sort of damage that is done to the brain in alcoholism occurs at a slow but steady rate when a person consumes any form of sugar- or starch-rich diet even with so-called complex carbohydrates.
Note that there are powerful associations with Alzheimer’s disease and gluten sensitivity as well.
When the brain and body learn, instead, to burn ketones as their primary source of fuel, the brain is spared much of this damage and is fed with a far more sustainable, reliable, and abundant source of energy to meet its constant metabolic needs.
One is far less subject to a “blood sugar low” and the mental, emotional, and physical symptoms associated with that state.
Blood sugar is thus essentially eliminated from the mood and cognitive equation.
The use of antiglycation nutrients can further protect from and help reverse, to at least some degree, these degenerative processes.