A new human study has found an easy way for us to slash our dementia risks by 15% over a 4-year time period, which probably compounds to a much higher risk reduction the earlier we start this method. In this article, we’ll unpack the study and explain how you can apply its lesson to protect your brain health.
Table of Contents
The New Study
This study, published just a couple of weeks ago, involved a massive research effort carried out in China. Scientists identified about 34,000 people living in rural villages who were over 40 and had high blood pressure. They divided them into two groups. One group just got regular care from their doctors. The intervention group was put on medications with a goal of lowering their blood pressure to less than 130. Their goal was to see how an aggressive approach to lowering blood pressure would affect rates of dementia [1].
And let me pause here for a moment because you might be wondering: What’s the connection between blood pressure and dementia? There are several distinct factors that can lead to dementia, but blood pressure is one of the most important. Here’s why.
The brain requires a large volume of blood to supply energy and oxygen. It’s filled with blood vessels, many of which are tiny and sensitive. Elevated blood pressure puts stress on the whole system, causing several problems at once.
It damages blood vessels, increases inflammation, and generates oxidative stress, which accelerates neuron aging. Plus, as the body responds to this damage over time, our vessels get stiffer and can form plaques. This makes the problem even worse. As we age, our brains gradually lose the ability to adjust to higher pressure and repair the damage.
This accumulated damage to the brain is a root cause of dementia.
So it makes perfect sense to see if lowering blood pressure can also lower dementia risk. (And it also makes sense to ask what a safe blood pressure level is. We’ll return to that question in a minute because the targets have changed.)
Here’s what the researchers in this new study discovered. At the end of four years, average blood pressure had fallen by about 30 points in the intervention group. This is compared to a fall of just 8 points in the control group [1].
So they hit their blood pressure target of under 130 in the intervention group. But here’s the crucial question. Did this make a difference when it comes to dementia?
It did. The intervention group had a 15% lower risk of dementia than the other group [1].
That’s an impressive result. And this was the impact after only four years. We know that the damage from high blood pressure is cumulative and builds slowly over time. So lower blood pressure over, say, 40 years is likely to have a much greater impact.
The Right BP Target
But I want to return to a question I raised a moment ago. Researchers picked a blood pressure target of 130 for this study. And getting below it obviously helped. But does that number represent a safe level? How high is high when it comes to blood pressure?
Two groundbreaking studies have completely changed our answer to this question. They show that we as doctors got it wrong. For decades we knew that high blood pressure was dangerous but we didn't realize just how dangerous even at levels that seemed okay.
For a long time, doctors believed that having a systolic blood pressure — that's the top number on your reading — up to 140 was perfectly fine. You may have even heard your doctor say that as long as your blood pressure is under 140/90 you’re in the clear. We used to think, “Okay, 120/80 is ideal, but 140? That’s still okay, right?”
We now know that having a systolic blood pressure near 140 is actually risky. It’s not just ‘okay’—it’s putting our lives in danger.
The reason doctors thought 140 was fine is that blood pressure tends to go up as we get older. So they figured a little higher was normal. But new research shows even that little extra pressure can cause big problems.
The first wake-up call came from the SPRINT study, which stands for the Systolic Blood Pressure Intervention Trial. This study was massive—over 9,000 participants—so the findings are hard to ignore.
The goal was to see if lowering blood pressure to below 120 would protect against heart attacks, strokes, and other problems better than using the older target of 140.
The people in this study were at high risk for heart disease, but they didn’t have diabetes or a history of stroke. They were split into two groups: One aimed for a blood pressure below 140, and the other aimed for less than 120.
Now, here’s where it gets really interesting—the results were so clear that they had to stop the study early!
The study was supposed to last 4-6 years, but after just 3.3 years, it was obvious that lowering blood pressure to below 120 made a huge difference. There was a 27% lower risk of having a heart attack, stroke, or dying from these causes each year [2].
And when it came to death rates alone, there was a 25% lower risk of dying in the group that aimed for 120 [3].
Let that sink in for a moment—a 25% reduction in the risk of death just by lowering blood pressure more aggressively. This isn’t a small improvement; it’s a game-changer.
But the story doesn’t stop there. Recently, another study in China tested these findings on an even larger and more diverse group—over 11,000 people. And it included those with diabetes and those who had already had a stroke.
Think of this study as a sequel to the SPRINT study but with an even bigger cast. And guess what? The results were just as powerful.
Lowering systolic blood pressure to less than 120 reduced the risk of heart attacks, strokes, and death from cardiovascular causes by 12% [4].
Plus, it cut the overall risk of death from any cause by 21% over three and a half years [5].
The takeaway is clear: the old 'normal' of 140 is no longer good enough. And the more aggressive target of 130 used in the first study we looked at isn’t ideal, either. Most of us should aim for a systolic blood pressure of less than 120 to really protect our health.
But these studies focused on heart attacks, strokes, and all-cause mortality. What about dementia risk? Do we know anything about the safe blood pressure level specifically for that? Thanks to recent research on this question, we now do.
One study is actually a follow-up analysis of the group used in the SPRINT study we looked at above. In this new study, researchers looked at the risks of developing dementia. Would they find the same pattern they did for heart attacks and strokes? The pattern was the same. Those who were given the lower blood pressure target had a 14% lower chance of developing dementia during the follow-up period [6].
This is a significant finding and another study adds one more piece of evidence that points in the same direction. It found that middle-aged women with blood pressure between 120 and 139 had increased evidence of cognitive decline a decade later. It wasn’t yet dementia, but it’s an indication their brains were suffering damage. The researchers suggest reducing blood pressure below 120 to reduce our risks of cognitive decline [7].
All of this gives us strong evidence that getting our blood pressure below 120 isn’t just the right target for our hearts. It’s the right target for our brains, too.
How to Lower
So what can we do to lower our blood pressure to a healthy level? Here are 5 of the most important actions we can take.
The first is to reduce our salt intake. The American Heart Association recommends that we have no more than about 1/2 teaspoon (or 1,500 milligrams) per day.
Compare that with the 3,500 milligrams the average American eats daily.
How significant is sodium intake? One study that looked at 85 different trials found a clear pattern: as sodium intake goes up, so does blood pressure [8].
The reason is simple. Sodium causes your body to retain more water, increasing the volume of your blood. If there is a greater amount of fluid in your blood vessels, it makes sense that the pressure would increase. It’s similar to the way a balloon stretches tighter and tighter as you blow more air into it.
A salt substitute is a good option for some people. This is a kind of salt that swaps out some of the sodium chloride in regular salt with potassium chloride. A large study in China found that making this simple switch cut strokes and lowered the overall death rate by 12% during the study period [9].
The second thing we can do to control blood pressure is to shift the way we eat. Researchers have developed guidelines called the DASH diet, which stands for “Dietary Approach to Stop Hypertension.” As you can tell from the name, it’s specifically designed to lower blood pressure.
One analysis looked at several types of interventions to lower blood pressure. It concluded the DASH diet might be the most effective way to lower blood pressure without using medications [10].
The DASH diet is simple. Choose vegetables, fruits, low-fat dairy, whole grains, chicken, fish, and nuts, while minimizing consumption of sweets, sugary drinks, and fatty cuts of meat. It’s high fiber, high lean protein, and packed with nutrients.
As an added bonus, when we follow the DASH diet, we’re also more likely to increase our intake of potassium through potassium-rich foods like spinach, bananas, peas, and beans.
Why is this a bonus? Because potassium helps lower blood pressure. It balances out sodium levels while also encouraging the walls of our blood vessels to relax. Its powerful effect is the reason I include it in MicroVitamin. Just because I take a supplement, though, doesn’t mean you have to also.
The third key strategy to lower blood pressure is adding exercise. I know how hard it can seem to get started, especially if you have been relatively inactive.
The good news is that even small changes can make a positive impact. I encourage my patients to start where they are and look for ways to add movement into their schedules. I recommend they try exercise snacks. They’re short bursts of physical activity that you sprinkle throughout your day—like mini-workouts instead of one long training session. Instead of carving out a 30-minute chunk of time to hit the gym, you might do a few sets of wall squats between meetings, for example.
I do an exercise snack during my 15-minute paperwork breaks at the clinic.
Finally, for overweight individuals, weight loss can be a powerful contributor to getting elevated blood pressure under control. One study showed that the greater the weight loss, the greater the reduction in blood pressure [11].
Fortunately, though losing weight can be challenging, making the changes we’ve talked about so far will make this much easier.
But if our weight is above target, despite optimizing our lifestyle factors, we can consider medications such as Ozempic to help on our weight loss journey. Taking medication isn’t a failure— it’s another tool to help reach our health goals.
And finally, if our lifestyle factors are dialed in, weight is perfect, but we still have a blood pressure above 120, then I have a discussion with my patients about the pros and cons of blood pressure medications. I emphasize that medication should be an addition to, not a replacement for, all the other steps.
References
1. https://www.nature.com/articles/s41591-025-03616-8
2. https://www.nejm.org/doi/10.1056/NEJMoa1901281
3. https://www.nejm.org/doi/10.1056/NEJMoa1901281
4. https://pubmed.ncbi.nlm.nih.gov/38945140/
5. https://pubmed.ncbi.nlm.nih.gov/38945140/
6. https://www.neurology.org/doi/abs/10.1212/WNL.0000000000213334
7. https://pubmed.ncbi.nlm.nih.gov/25814553/
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8055199/
9. https://jamanetwork.com/journals/jamacardiology/article-abstract/2829790
10. https://pmc.ncbi.nlm.nih.gov/articles/PMC7792371/
11. https://www.uptodate.com/contents/image?imageKey=NEPH%2F60178&topicKey=PC%2F3852&source=see_link
