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One Major Effect the Keto Diet Has on Cancer, New Study Suggests

Ditch the bread for brain health.
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According to a recent study from the American Academy of Neurology, following a modified ketogenic (keto) diet could be beneficial for those who have been diagnosed with a brain tumor.

The main purpose of this investigation was to determine if the keto eating pattern was doable for adults after completing their treatment plan (radiation and chemotherapy) for astrocytoma—a type of cancer that stems from cells called astrocytes, which support nerve cells, as defined by the Mayo Clinic.

Since glucose causes cancer cells to divide and multiply, the research team focused on the low-carb, low-sugar keto diet based on the theory that cancer cells cannot utilize ketones for energy.

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During the eight-week study period, the patients were instructed to follow one version of the keto diet—a modified Atkins (low-carb) diet for five days a week, followed by two days of intermittent fasting (where they could consume up to 20% of their recommended daily caloric intake). The volunteers worked with a dietitian throughout the trial.

As for the results, which were published in the online issue of the journal Neurology, not only was this eating style well-tolerated among the majority of the participants, but the study authors noted that several positive changes occurred in both the body and the brain. These changes included a decrease in hemoglobin A1c levels, insulin levels, and fat body mass, along with an increase in lean body mass, as well as concentrations of ketones and metabolic changes within the tumor.

Table of keto diet foods on a table

'There are not a lot of effective treatments for these types of brain tumors, and survival rates are low, so any new advances are very welcome," said Roy E. Strowd, MD, MS, MEd, of Wake Forest School of Medicine in Winston-Salem, N.C., and a Fellow of the American Academy of Neurology, in a press release.

"Of course, more studies are needed to determine whether this diet can prevent the growth of brain tumors and help people live longer, but these results show that the diet can be safe for people with brain tumors and successfully produce changes in the metabolism of the body and the brain."

Interestingly enough, this isn't the first time scientists have looked into a possible association between the keto diet and brain health, says Sarah Koszyk, MA, RDN, registered dietitian, sports nutritionist, and author of "365 Snacks for Every Day of the Year."

"These previous studies found positive results in regards to the brain being able to use ketones as an alternative energy source instead of carbohydrates," she states. For example, research published in the journal PNAS discovered that dietary ketosis was shown to boost brain activity in adults and could ward off the effects of brain aging.

Koszyk further explains that there are some other health benefits to going keto, such as losing weight, saying that "fat fills us up so we feel satiated after eating, which also helps with controlling hunger levels."

The diet can also help regulate blood sugar levels. "It can beneficial for people with insulin resistance, such as women with PCOS or those living with type 2 diabetes," she adds. "The ketogenic diet has also been used to reduce seizures in people who have epilepsy."

Many saying no to carbs so he is cutting carbs and choosing a keto diet instead

However, there can be some downsides to this popular eating pattern. While fat is your friend, the type of fat you place on your plate can make a difference in your overall well-being.

"Heart-healthy fats, such as monounsaturated fats [like olive oil, avocado, and peanuts] and omega-3 fatty acids [such as salmon, oysters, and chia seeds] are fabulous for our health," says Koszyk. "Unfortunately, choosing to consume higher amounts of saturated fat [fatty beef, cream, butter, and cheese] can lead to increased risk of heart disease and stroke."

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Also, she states that a limited intake of higher-carb fruits (such as bananas and mangoes), vegetables (like beets and sweet potatoes), and certain fiber-rich foods (including quinoa and oatmeal) can lead to unwanted side effects, such as fatigue and constipation, along with vitamin and mineral deficiencies. And since there's little room for error on the keto diet, sticking to the plan can be quite the challenge.

"For a person to get in a state of ketosis, they have to be very diligent and consistent with their carb intake in order to allow the body to use fat for fuel," explains Koszyk. "So if someone has a 'cheat' day or simply eats more carbs than recommended, their body will go back to using glycogen as their primary energy source—and that is not the goal."

Yet in the case of this latest research from the American Academy of Neurology, she believes their initial findings hold some promise. "The study had a very small sample size—only 21 people completed the study and only 10 people actually followed the full ketogenic diet plan—so more research is needed to determine better conclusive results," says Koszyk. "But this study is a good start."

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Amy Capetta
Amy Capetta has been writing articles on healthy living for more than two decades. Read more about Amy
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