From stress to sleep and forgetting about certain foods in your diet, here's why your blood-pressure numbers may be on the rise.

You might not be thinking about your blood pressure right now—but you should. "Blood pressure is a silent killer. Most people have no signs or symptoms, and unless their blood pressure is measured, it's easy to miss," says Jill Weisenberger, a registered dietitian nutritionist who specializes in diabetes and heart health. Overtime, high blood pressure can damage your heart, brain, kidneys and eyes, says the Centers for Disease Control and Prevention (CDC).

Diet choices and lifestyle habits play an important role in keeping blood pressure levels normal, which is considered less than 120 mm Hg for systolic (top number) and less than 80 mm Hg for diastolic (bottom number).

Here are some of the top surprising factors that Weisenberger sees that may behind your rising numbers:

an illustration of a digital blood pressure monitor with numbers climbing up
Credit: Getty Images / Malte Mueller, Freepik / hannazasimova

1. You're skimping on fruits and vegetables

When you think about high blood pressure, you might assume it's all about your sodium intake. Sodium raises blood pressure because it pulls water into blood vessels, explains the American Heart Association (AHA). Increased blood volume means that there's more coursing through vessels, which raises your blood pressure. Potassium, on the other hand, is the counter to sodium, helping to flush the mineral out of the body, per the AHA.

Potassium is where you may be falling short. "One of the biggest problems I've seen in my practice over the years is that people are not eating enough potassium," says Weisenberger. "When someone has low potassium intake—especially in the presence of high sodium intake—they're much more likely to have high blood pressure," she explains. Potassium is considered a nutrient of "public health concern" by the USDA because, in general, we're not getting enough of it, likely because just one in 10 adults are eating adequate amounts of produce, notes the CDC.

While there are certain foods known for their potassium (like bananas), you can get the potassium you need through a variety of plants, including fruits, veggies and legumes. The number you should eat per day depends on a variety of factors, but the USDA suggests filling half your plate with fruits and veggies at each meal.

2. You're not checking for the hidden sodium

Think you'll automatically know when a food or meal is high in sodium? "People think that they can taste a high sodium food. They cannot. If something is baked or cooked in salt, the salt becomes mixed within the dish and it doesn't go directly to your tastebuds, as it does in the case of chips or [salted] peanuts," says Weisenberger. She notes that innocent-sounding foods like instant pudding, instant oatmeal and lemon-pepper seasoning are all hidden sources of sodium.

A good rule of thumb is to look at nutrition labels, specifically percent daily value for sodium. 5% daily value is considered "low" whereas 20% is considered "high". Go for options that have a lower amount of sodium per serving.

Restaurant dishes are other big culprits. To choose lower sodium foods, Weisenberger suggests asking if the chef can cook or use a light hand with salt—and if they're willing to do it. "It's not going to be easy. If you're truly trying to follow a low-sodium diet, it pays to make friends with people who work at restaurants," she says.

3. You're missing out on sleep

It's easy to shove sleep aside to make room for everything else you need to do in your day, but enough shut-eye is necessary for healthy blood pressure. "Not getting enough sleep is like a physical pain to the body, and it can raise blood pressure," says Weisenberger. People who say their sleep quality is poor are 48 percent more likely to also have hypertension, found a meta-analysis in The Journal of Clinical Hypertension in 2018. The effect goes the other way, too: people with hypertension tend to have worse sleep.

In addition, sleep also changes how you eat. No problem if the poor sleep munchies had you reaching for carrot sticks, but you're more likely to eat processed (and high-sodium) snack foods or high-sugar options, another factor that plays into the development of high blood pressure, notes the AHA. Poor sleep triggers changes in appetite hormones that prompt you to make less healthy choices—and overeat, explains Weisenberger. Aim for at least 7 hours of sleep each night, per the CDC.

4. You're hitting happy hour a little too hard

Alcohol, especially wine, has a heart-healthy reputation. However, compared to those who skip alcohol altogether, for men and women consuming more than two alcoholic beverages per day, their risk of having high blood pressure is 51% and 42% higher, respectively, according to a review and meta-analysis published in 2018 in the Journal of the American Heart Association.

While the reasons why alcohol might raise blood pressure are still being looked at, alcohol may affect the way blood vessel walls contract and relax, and it may also generate free radicals that damage the cells that line blood vessels, notes research. Even though women may be less prone to the blood pressure upping effects of a glass of wine, it's still recommended that women stick to one drink per day and men limit themselves to two.

5. You're not dealing with stress

Contrary to popular belief, stress is not a direct cause of high blood pressure, says Weisenberger. In reality, stress is more of a transient cause, e.g. you get a bad phone call and your blood pressure surges; after you relax, it calms, she explains. That said, when you're stressed out, you lose focus on those healthy habits you're trying to establish. "In the same way with sleep, when you're stressed, it's harder to muster the motivation to go for a walk or jog or prep a meal from scratch," she explains.

The ultimate goal would be to aim for a lifestyle that supports a healthy heart. "Engaging in regular healthy habits, such as good sleep, meditation, and time with friends, yourself and nature, will improve blood pressure indirectly," says Weisenberger.