Is there a link between dementia and diet?

Dementia is the most common cause of disability and death across the globe. There is no way to stop it. According to recent studies, dietary factors may influence dementia risk and progression. We analyzed the data and looked at how you might help minimize your risk of dementia.

dementia and diet

Dementia affects more than 55 million people globally, according to the World Health Organization (WHO), with 10 million people diagnosed each year. Alzheimer’s disease affects about 60-70 percent of people with dementia worldwide, and it affects nearly 6 million people in the United States.

In some age groups, it may be the third biggest cause of death after cancer and heart disease.

The WHO predicts that the number of people living with dementia will climb to 78 million by 2030 and 139 million by 2050 as the world’s population ages.

Diabetes, obesity, and heart disease, all of which can increase the risk of dementia, are all on the rise, according to existing data.

Memory issues, loss of cognitive function and coordination, and personality changes are the basic signs of dementia. Aging is the most significant risk factor for dementia — more than 90% of people with dementia are over 65 — but other variables have a role as well.

There is presently no cure for dementia, and most therapies only help to relieve symptoms rather than reduce the disease’s progression. So, are there any strategies to mitigate this risk?

Is it possible to lower risk by eating a “healthy” diet?

Maintaining a healthy and fit lifestyle can help to minimize the incidence of dementia, and eating is a big part of that.

Dr. Christopher Weber, head of global science efforts at the Alzheimer’s Association, said in a message for MNT:

“Research looking at the relationship between diet and cognition is well-established. There is strong evidence to suggest that what is good for the heart is good for the head, and we know a healthy diet is good for the heart.”

A Mediterranean diet has been shown to boost cognitive function in some studies. This diet consists primarily of fruits and vegetables, nuts and seeds, olive oil, and fish, with only little amounts of dairy, eggs, and red meat, as well as a modest amount of red wine.

A Mediterranean diet has been linked to enhanced cognitive functioning and delayed the progression from moderate cognitive impairment to dementia, according to new research.

The MIND diet

The MIND diet is an alternative to the Mediterranean diet (Mediterranean-DASH Intervention for Neurodegenerative Delay). Green leafy vegetables, other vegetables, nuts, berries, beans, whole grains, seafood, chicken, olive oil, and wine are all part of the diet.

This diet emphasizes the relevance of foods and nutrients linked to the prevention of dementia.

Diet studies have the disadvantage of being observational, and people frequently assess their diet using self-reported questionnaires. Researchers, on the other hand, have shown a link between these diets and increased cognitive function.

According to one study, participants who followed the MIND diet had much less cognitive impairment. In a study published in 2021, researchers discovered a link between MIND diet score, cognitive resilience, and cognitive function.

The researchers discovered that increased cognitive function was independent of brain diseases observed during post-mortem examinations.

“The Mediterranean diet and the MIND diet have been demonstrated to be beneficial to brain and heart health in clinical research,” Dr. Weber said. To assist lower the risk of cognitive decline, the Alzheimer’s Association recommends everyone to consume a healthy and balanced diet.”

Processed food may increase risk

One of the current villains is processed food. To be healthy, experts advise that we consume a well-balanced, varied diet rich in fresh foods. But, may a high-processed-food diet put you at risk for dementia?

“There is […] strong evidence linking poor diet (for example, eating a diet high in unhealthy fats and sugar) and increased risk for dementia.”

– Dr. Christopher Weber

A high-refined-carbohydrate diet raises the risk of dementia and Alzheimer’s disease in animal models. This impact was mirrored in a human research in France, which found that older people who ate a daily snack high in refined carbs were more likely to acquire dementia.

Another study found a relationship between dementia and processed meat items including sausages, salami, and bacon. Processed meat consumption elevated the relative risk of all dementias by 44% and Alzheimer’s disease by 52%, respectively.

However, this was an observational study, like all the others, and the risks reported are relative rather than absolute. The findings, according to one expert, “would not persuade me to give up my breakfast bacon.”

Should you take supplements?

Vitamin and mineral supplements are frequently promoted as a means to compensate for a poor diet, but is there any proof that they can help prevent dementia?

A recent study discovered that when older male rats were fed a processed food diet heavy in refined carbs, their learning and memory abilities deteriorated. A group of rats fed the same food but supplemented with omega-3 fatty acids had no memory difficulties.

The findings were explained by the study’s authors in terms of the inflammatory response induced by processed foods. Omega-3 is known to reduce inflammation, which could explain the impact in the rats who were given it.

There is, however, little further evidence that supplements have an effect on dementia. A healthy diet and regular exercise, according to the WHO, will likely have more significant consequences.

Is it better to drink or not to drink?

The connection between drinking and dementia is not completely understood. While severe alcohol use is linked to the development of dementia, the impact of moderate alcohol consumption is still unknown.

The majority of research demonstrate a link between moderate alcohol use and a lower risk of dementia, especially in red wine consumers.

Reduced heavy alcohol usage could be an effective dementia preventive strategy, according to two systematic evaluations, one of which assessed results from 26 research.

They did find, however, that individuals who completely refrained from alcohol had a higher risk of dementia than those who drank in moderation.

As a result, while moderate drinking may have some protective effects, no observational study can rule out all other factors. It’s possible that moderate drinkers eat better, exercise more, and are in better overall health.

A study in New Zealand looked at the effects of moderate drinking on older persons, controlling for socioeconomic level, but found no indication of a link between moderate drinking and better health.

So maybe that protective effect is merely wishful thinking on the part of those of us who like a drink now and then!

The microbiota and inflammation

Memory loss has been related to inflammation in studies, and this is a topic that is generating a lot of buzz.

“This accords with the ‘inflammaging’ notion that is getting a lot of popularity,” says Prof. Tim Spector, Professor of Genetic Epidemiology at King’s College London and Zoe Study head.

Inflammation and the gut microbiome have been linked. A link between the gut microbiome and dementia has been discovered in several clinical trials.

In a cross-sectional study conducted in Japan, researchers discovered a substantial difference in the microbiome of dementia people compared to those who did not have the disease.

Bacteroides, a species known to alleviate inflammation, was found in significantly lower numbers in dementia patients. They also had a much higher number of microorganisms (enterotype III) linked to dementia.

These findings are backed up by two more investigations. One analyzed looked at the metabolites produced by the gut microbiota and discovered that people with dementia had considerably different metabolites than those who did not have dementia.

The effects of the gut microbiome on microglia and cytokine release, both of which have consequences in inflammation and dementia, were highlighted in a second study.

“There are large numbers of studies that are pointing in the same direction. People with dementia have sub-optimal microbiomes. The picture is of not only reduced numbers of species but also increased numbers of inflammatory species.”

– Prof. Tim Spector

Diet and company

Diet and the gut microbiome are linked, which could explain why the Mediterranean and MIND diets have demonstrated to reduce dementia risk and development.

“Reduced [microbiome] diversity and [more] inflammatory species are related to poor diet, generally low in fiber and diversity of plants,” Prof. Spector told us. “With elderly people, there’s often a tipping point, such as losing a partner. The diet reduces in quality and diversity. That can accelerate cognitive decline.”

He did, however, mention the possibility of reverse causality. People who are in the early stages of cognitive decline may lower the quality of their diet, hastening the process.

He continued, “Studies of centenarians have revealed that they generally live in locations with an excellent culinary culture and a lot of socializing.” “It has nothing to do with fats.” It’s not about carbs or calories; it’s about having access to fresh, varied food. You rely on your gut microorganisms to keep your immune system in check and keep inflammation at bay?”

Is it possible to lower your dementia risk?

The quick answer is that diet is likely to play a role. A varied diet rich in plants is increasingly being shown to maintain a diverse gut microbiota. In addition, having a diverse gut microbiome helps to prevent the inflammation linked to dementia.

“Poor diet harms microbes, which harms the immune system with these knock-on effects of cognitive decline. In dementia, inflammatory aging is the current theory. It’s partly triggered by the immune system which involves the microbes and diet.”

– Prof. Tim Spector

So, until randomized control trials can verify how diet affects dementia, it’s probably preferable to follow a diet that lowers your risk of heart disease and maintains your microbiota while still getting enough of exercise.

Although the jury is still out on moderate alcohol consumption, there is strong evidence that excessive alcohol drinking raises the risk of a variety of health conditions, including dementia.

“While we continue to learn more about the lifestyle factors that have the biggest impact on our overall risk,” Dr. Weber said, “there are things we can do today to reduce our risk of cognitive decline as we age.” Eating a heart-healthy diet, exercising regularly, and staying cognitively engaged are just a few.”