Steps to Reduce Your Risk of Dementia

Evidence-based, just not Instagram worthy

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In my last post I discussed the fact that menopause hormone therapy (MHT) is not recommended by any menopause society to prevent dementia. Sometimes, when people hear/read this they feel discouraged, because they’ve been led to believe that only estrogen will help, and so when the state of the medical evidence is revealed it can be a bit of a, “What now?” moment. I’ve received many comments from people who were very discouraged as they had been led to believe from menopause influencers that estrogen was the best thing to protect the brain. But all of the guidelines are essentially identical to this joint one from the British Menopause Society, Royal College of Obstetricians and Gynecologists, and the Society for Endocrinology.

Do not despair! 

There are many modifiable factors when it comes to preventing dementia. This information I am going to share with you comes from the 2024 Lancet Commission on Dementia, which is an update from their 2020 report. In 2020, the authors identified 12 modifiable evidence-based factors to reduce dementia, and for 2024 they have expanded that list to 14. Together, the Commission estimates that almost 50% of cases of dementia could be eliminated if all of the recommendations were implemented. This means there are things you can do right now to reduce your risk of dementia, and, hey, if you are already doing them, then great!

The Lancet Commission broke risk factors down into three categories based on when they have their impact: early life (< 18 years), midlife (18 to 65 years, yes that’s a bit of range), and late life (> 65 years). It’s also important to consider that some factors are more individually modifiable than others, for example air pollution is a risk factor important in later life, and while we can all work to reduce air pollution, including voting for politicians who believe air pollution is the health crisis that it is, there isn’t much that most of us can do in the immediate future to dramatically fix our air quality today. Then again, the more individuals decide to take up this commitment, the more we all benefit and the sooner. Another important point is that while the studies only showed a link between dementia and air pollution in older individuals, this may be because of the populations studied. There is plenty of evidence showing air pollution is harmful to health overall, so it’s never too late to start working on reducing it.

Before we get into the specifics of the list for midlife, I want to address the one that starts in early life: education. It’s clear from many studies that people who receive more education are less likely to get dementia. It is believed that cognitive reserve protects the brain. In fact, less education in early life is such an important cofactor that it may ultimately be responsible for 5% of cases of dementia. Now consider how girls and women are able to access education around the world compared with boys and men. This means at least some of the increased incidence of dementia among women vs men is due to the patriarchy, as it is systems put in place by men than have resulted in less access to education for women. 

Discrepancies in health and education being risk factors for dementia are important to consider when thinking about some of the observational data that have been aggressively hyped to suggest menopause hormone therapy reduces the risk of dementia (and too be clear, there are observational studies that indicate it doesn’t reduce the risk of dementia, covered in my post that I referenced earlier). For example, someone with significant cardiovascular disease may not be a candidate for MHT, and in addition, their cardiovascular disease puts them at greater risk for dementia. This means that people who are more likely to get dementia could be overrepresented in the not-taking-MHT group of an observational study, making it falsely appear that MHT lowers the risk of dementia. The same could go for education. People with more education may be more likely to be able to access health care, so they are more likely to get care for hot flashes and to have adequate treatment for conditions like high blood pressure and diabetes, lowering their risk of dementia. Meaning in observational studies, people who are less likely to get dementia may be over represented among those taking MHT. 

The 14 modifiable factors for prevention of dementia outlined by the 2024 Lancet Commission share some common pathways and are suspected of working by doing one or more of the following: 

• Decrease vascular damage

• Reduce dementia neuropathology

• Reduce stress and inflammation

• Build cognitive and brain reserve

Here, I want to focus on modifiable midlife factors, which are estimated to cause about 30% of cases of dementia. 

Modifiable Midlife Risk Factors for Dementia

• Hearing loss, and the greater the hearing loss, the greater the risk. Hearing aids have been shown to reduce or slow cognitive decline and reduce the risk of dementia, and the benefit may be greatest for people who have other risk factors. 

• High LDL cholesterol, there is good data here to support a link with dementia. While most of this is from observational studies, unlike with MHT, there is a consistent effect in multiple studies. Statin use is also associated with a lower risk of dementia and specifically Alzheimer’s and the effect is true for both women and men. 

• Depression has been linked with dementia, and untangling the connection can be challenging as depression can also be an early symptom of dementia. There are several potential mechanisms, such as an increased inflammatory response, or isolation, but the actual cause of the connection is unknown. The U.K. Biobank study suggests that treating depression, by psychotherapy, medications, or both, reduces the risk of subsequent dementia. 

• Traumatic brain injury (TBI), even one mild traumatic brain injury (concussion) may increase the risk. While a lot of work here has focused on sports (wear a helmet on a bike), one cause of TBI that does not get enough attention and is more likely to affect women is intimate partner violence.

• Physical inactivity is linked with dementia, although whether the protective effect of exercise is via a direct effect on the brain via an increase in blood flow or reduced inflammation or an improvement in cardiovascular health isn’t known. 

• Diabetes is associated with dementia primarily when the onset is during midlife. There is a fair bit of emerging evidence suggesting that treating diabetes with GLP-1 agonists (drugs like Ozempic) may reduce the risk, although the exact reason for this isn’t yet known.  

• Smoking seems to be bad for almost every medical condition, and dementia is not exception. The good news is that stopping smoking can help mitigate its negative impact.  

• High blood pressure (systolic, which is the top number, > 130 mmHg) is associated with dementia, and treating it can lower the risk. 

• Weight, both obesity and being underweight are associated with an increased risk of dementia. 

• Sustained heavy alcohol use (more than 168 g or 21 UK units or 12 US units/week) is associated with a higher risk of dementia. One UK unit is 8 g of alcohol and one US unit is 14 g of alcohol, while in Australia one unit is 10 g and in Canada it’s 13.5 but sometimes 13.6 (and why it’s different everywhere makes no sense to me, but probably related to some fascinating, yet obscure piece of history). In the US, 14 g is 5 ounces of wine or 12 ounces of regular beer or 1.5 fluid ounces of hard liquor.   

Social isolation was identified as a modifiable risk factor, but it has the greatest impact in later life, so not our immediate focus here but something very important to think about as we age. Vision loss is also a modifiable risk factor, but again the impact was in later life. 

What about sleep? I admit, I was surprised to not see it on the list. Apparently, the data linking reduced sleep with dementia isn’t robust, although a short term lack of sleep does have a negative impact on cognition (which, to be clear, is not dementia). That being said, obstructive sleep apnea is associated with an increased risk of dementia.

Taking the Next Steps

Think about all of these modifiable risk factors and your current health. Here are the practical things you can do to help lower your risk of dementia: 

• Get your hearing tested. I did that earlier this year because I really thought my hearing was impaired as I need subtitles when I watch any streaming show. It turns out it’s just the weirdly loud music or my inferior sound system, because my hearing is okay, and, on reflection, I don’t have that issue at the movies. 

• If you haven’t been screened for diabetes or had your LDL checked in the last 1-2 years, make an appointment to get that done. Typically the test for diabetes is a hemoglobin A1C or fasting glucose, but if you have polycystic ovarian syndrome, make sure to get a 2 hour glucose tolerance test as this is more accurate for you. If you have an elevated LDL, talk with your provider about statins and if you have diabetes, talk with your provider about the best treatment for you. Reducing saturated fats and eating more fiber are good strategies to help keep your LDL in a healthy range and are part of a heart healthy diet. Remember, if it’s good for the heart it’s generally also good for the brain! 

• If you haven’t had your blood pressure checked in the past year, try to get it done (and then have it checked at least once a year). You can often do that at a drug store, avoiding the need and potential expense of an office visit. I have a blood pressure cuff at home, which makes it all so much easier and can be very helpful for people who only have high blood pressure at the doctor’s office (white coat hypertension). If your systolic blood pressure is over 130, talk with your provider about therapy. 

• Get screened for depression. This is especially important if you have any symptoms of depression, such as insomnia or sleeping too much, reduced interest in things, mental and physical fatigue, changes in appetite, or difficulty concentrating. 

• Wear a helmet while bike riding and think about other risk factors that you might have for TBI. 

• Do your best to start and maintain a regular exercise program. The maintenance part is the hard part, or it is for me anyway. Don’t worry about which exercise, because we don’t have good data to make specific recommendations, but it seems any exercise is beneficial, be it cardio or resistance training. 

• If you are in an okay place to think about your weight, consider if you are able to make changes if you have obesity or are underweight. 

• If you are a smoker, talk with your provider about getting help quitting. 

• Evaluate your alcohol intake and consider reducing it if you are a heavy drinker. I used to have 3-4 drinks a week, but the data on breast cancer convinced me to have less. I have 1-2 drinks a month now, and some months don’t have any. I honestly don’t miss it. Now, I pour my Diet Coke of flavored soda water into a wine glass and I feel like I am doing something special, and honestly, that works great for me! 

• If it’s been a couple of years, get your vision checked. While vision problems were more applicable for later life, why wait? If you need glasses or a new prescription you will almost certainly be happier when your vision improves. I just had my eyes checked two months ago and have new glasses, and wow. All I can say is I feel like I am paying a price for having great vision until 52. 

• Ask your provider if you should be screened for sleep apnea.

And remember, this list is not all of none! Any change you can make will be beneficial. 

There are many things to do for brain health, but none of them are particularly Instagram worthy. Or at least I’ve never seen a viral video about getting screened for depression or the importance of checking your LDL. Lots of “brain health” supplements, though.

Which reminds me, you know what isn’t on the list? Supplements.

As always, the information here is not direct medical advice. If you have questions, please feel free to leave them below. I try to reply to the easier ones directly in the comments (obviously, again, not individual medical advice). For those questions that are more complex, I tuck them away to incorporate them in future posts.

References

Livingston G, Huntley J, Liu KY, et al. Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. The Lancet 2024, July 31. 

Zhu J, Ge F, Zeng Y, Qu Y, et al. Physical and Mental Activity, Disease Susceptibility, and Risk of Dementia: A Prospective Cohort Study Based on UK Biobank. Neurology. 2022 Aug 23;99(8):e799-e813. doi: 10.1212/WNL.0000000000200701. Epub 2022 Jul 27. PMID: 35896434; PMCID: PMC9484730.