A “milkshake” of sorts can improve cognitive function in people at the early stages of Alzheimer’s disease by giving their brain a ketogenic boost, a new study has found.
The research involved a group of older adults with cognitive impairment who were given the drink twice a day. After six month, they showed higher levels of brain energy and scored better on tests for such mental skills as memory, language and speed of processing.
The finding shows that when Alzheimer’s strikes, ketones can be used as a back-up fuel to help defend the brain against the disease, according to lead researcher Stephen Cunnane.
“We consider this to be significant,” says Cunnane, a physiologist at the University of Sherbrooke Research Center on Aging in Quebec. “One of the few ways anyone has been able to show you can potentially slow down the progression of Alzheimer’s is by coming to the energetic rescue of the brain.”
The study was published in the May issue of Alzheimer’s & Dementia, the journal of the Alzheimer’s Association.
A ketogenic diet, which is low in carbs and higher in fat, is increasingly being promoted as a boon to brain health. But the results of this study go well beyond that, demonstrating that a daily drink that produces ketones can refuel the brain of dementia patients or people at higher risk of dementia.
A normal, healthy brain draws the power it needs from a simple sugar in the blood called glucose, which we get in ample supply from the food we eat. Such staples as bread, rice and pasta are high in carbohydrates, which our body turns into glucose.
However, as we age, our brain cells becomes less able to obtain and metabolize that glucose, which can lead to minor memory problems, or “senior moments,” as we call them.
But here’s a much harsher reality. When an older adult develops dementia, the ability of the brain to metabolize glucose drops precipitously and unrelentingly.
“It’s starving of glucose; it’s starving of energy,” Cunnane says.
But there’s evidence that even in the case of Alzheimer’s, the brain retains the ability to use another source of energy — called ketones — as back-up fuel.
The bad news is that most of us don’t get enough ketones from our diet to help the brain out much. “If you are eating carbohydrate-rich three meals a day, your ketones are only contributing a maximum of 5 percent to your brain energy metabolism,” Cunnane says.
What Cunnane and his fellow researchers wanted to confirm was that if people with cognitive problems consumed a drink producing higher levels of ketones, that alternative fuel would not only reach the brain, but result in a measurable increase in brain energy — bringing some improvement in cognitive function along with it.
“It’s something we’re trying to exploit to get around the glucose problem,” Cunnane says.
So they conducted a study involving about 50 men and women over the age of 55 diagnosed with mild cognitive impairment.
The participants were divided into two groups, and half received a bottled drink that consisted of skim milk containing a pair of fatty acids called caprylic acid and capric acid, both of which are ketogenic. They drank the concoction twice a day, usually with breakfast and dinner. The other half received a placebo beverage that was indistinguishable from the keto drink but produced no ketones.
Before and at the end of the study, the participants underwent a variety of tests, including PET scans and cognitive exams.
After six months, those who received the keto drink had levels of ketones in the brain that were twofold higher. More importantly, those individuals scored better on cognitive tests, including improvements in episodic memory, language and executive function, which refers to decision-making abilities.
“I’m happy our idea was confirmed, and that we could see a relationship between that twofold increase in brain ketones and the cognitive outcomes, that the two seemed to be related,” Cunnane says. “I consider that to be significant in a proof of concept sense, in that you can help close the brain energy gap caused by lower glucose uptake with ketones and you can have an effect on cognitive function in the early stage of the disease.”
Cunnane says this same benefit could also be achieved by eating a ketogenic diet. In fact, that could potentially be even better because such a diet provides a steady source of ketones to the brain throughout the day. A keto drink only provides a temporary ketone boost lasting two to three hours.
“If you take the drink at breakfast, by lunch the ketones are back at zero,” he says. “Even this sporadic change in ketones is helpful, but it’s not constant like with a ketogenic diet.”
On the other hand, adopting a ketogenic diet requires a dramatic change in eating habits, one that many people find hard to make. A keto drink is a far easier and more convenient way to offer the ketogenic benefit to someone experiencing serious cognitive problems, Cunnane says.
“The advantage is you can give them a prepared drink, so they don’t have to think too much about it,” he says. “They say, ‘OK, I take 4 ounces of this in the morning and I take 4 ounces of this in the evening and I don’t have to change what I eat, and I’m getting this dose of ketones, so what could be better than that?’”
Another goal of the study was to determine whether a keto drink taken twice a day is something that is well-tolerated in older adults. Researchers were pleased to see that nearly 80 percent of those who received the drink were able to take it without problems, which would be considered a good level of tolerance for an experimental drug.
“To make this ‘milkshake,’ as you might say, and for 78 percent to complete the study after six months, we were very pleased,” Cunnane says.
That’s important, because it demonstrates that a keto drink can be both safe and well-tolerated, which means people with cognitive problems can consider trying it even while further research continues.
The drink used in the study contained 12 percent medium-chain triglycerides, or MCTs. Cunnane says there are many MCT products on the market right now that contain MCTs, and he says their use has long been accepted.
“You can buy medium-chain triglycerides in health food shops and maybe even in drug stores,” he says. “There is no issue with the FDA. MCTs have been used in clinical nutrition for 50 years.”
However, not all products marketed as MCTs are actually ketogenic. Only MCTs that have a carbon count of 8 or 10 produce ketones. MCT products with a higher carbon count of c12 or c14 could be less expensive, but don’t contain ketones.
“There are some products that are pure c8 ostensibly, and they are more ketogenic,” Cuccane says. “Coconut oil contains MCT as well but they are long-chain MCTs and they are not ketogenic. So people can ask for technical info, so they know they are getting the c8 as opposed to the c12 or c14 in coconut oil.”
He says coconut could still be beneficial for cognitive issues in aging adults bith this hasn’t been adequately tested. If there is a beneficial effect, it probably isn’t via ketones.
Cunnane also wants to keep the findings of the study in perspective for those dealing with cognitive impairment or dementia.
“I want people to understand that there’s no magic in slowing down Alzheimer’s disease,” Cunnane says.
“Our study does not show you can slow down Alzheimer’s. It shows that you can improve the brain’s energy status and get some better results on cognition,” he says. “But it’s going to take 10 years to show that we can actually slow down Alzheimer’s. I don’t want people to over-interpret and expect miraculous results.”