There are two types of people in the world: those who brush their teeth before breakfast and those who brush their teeth after breakfast. But which group is right? Well, like most health-related questions, it depends.

When is the best time to brush your teeth?

While there are varying opinions within the dental community, Dr. Jossen Gastelum, a Phoenix-based dentist better known as @doctorjossen on TikTok, is a proponent of brushing your teeth before breakfast.

“In my opinion, brushing your teeth before breakfast helps to add a protective coating onto your teeth and can even help to stimulate your saliva before you eat breakfast,” Gastelum tells Fortune. “When you’re sleeping, your salivary flow decreases, and many people experience dry mouth for various reasons. Saliva helps to buffer out the acidity in your mouth. This means that your teeth are more prone to acid attacks in the morning right when you wake up—not to mention morning breath, too.”

But if you insist on brushing your teeth after your first meal of the day, Gastelum suggests waiting at least 30 minutes after you’ve finished eating, as the acids in your food and drinks (especially coffee) can damage the enamel, while the American Dental Association recommends waiting at least an hour after eating to brush your teeth.

“Your saliva takes about 30 minutes to buffer out the acids in your mouth back down to safe levels,” he says. “In the interim, you can swish with either water or an alkaline mouth rinse like TheraBreath to help neutralize the acids in your mouth while your saliva gets to work.”

How often to brush your teeth

You should aim to brush your teeth at least twice a day: once in the morning and once before going to bed.

“Both times are equally important in my opinion, but before bed is especially crucial because you want to brush away all the plaque accumulated during the day,” says Gastelum. “I like to tell kids (and some adults): You brush your teeth at night to keep your teeth, and you brush your teeth in the morning to keep your friends.”

If you want to squeeze in a midday toothbrushing, say, after lunch, Gastelum recommends waiting 30 minutes after your meal to avoid brushing acids into your teeth. But keep in mind that more brushing doesn’t automatically equate to better oral health.

“I think most people’s first instinct is that the more they brush, the better,” he says. “I agree that mechanical disruption of plaque is the best way to prevent cavities and improve gum health, but it is not necessary to obsessively brush as long as you’re doing it well in the morning and at night before bed.”

The best way to brush your teeth

A soft or extra soft toothbrush is recommended by most dentists. Adults should use a pea-size amount of toothpaste and hold the toothbrush at a 45-degree angle toward your gums while brushing back and forth in short strokes to get every tooth. Aggressive brushing can result in gum recession and enamel wear.

“If you have an electric toothbrush, use very gentle pressure and glide the toothbrush on each tooth at a 45-degree angle toward the gum on the outside and inside surfaces, and then straight onto the top surfaces of your teeth,” says Gastelum. “Let the brush do all the work—that’s what you bought it for.”

You’ll also want to change your toothbrush every three to four months, or anytime after you’ve been sick.

Other ways to protect your teeth

Good oral health is indicative of overall health as well. Recently, researchers have linked gum disease to cardiovascular disease, diabetes, dementia, Alzheimer’s disease, and even erectile dysfunction.

In addition to regular brushing, flossing is important for keeping your gums at optimal health. Flossing at least once a day can help reduce your chances of getting cavities in between your teeth.

“Water flossers, for example Waterpik, are great adjuncts as well, which really improve gum health, especially in patients with low dexterity,” says Gastelum. “Tongue scraping is also very underrated and important for reducing bad bacteria in your mouth.”

Using mouthwash five minutes before brushing your teeth can help counter morning breath, although alcohol-based mouthwash can dry out your mouth.

If you struggle with maintaining a consistent toothbrushing routine, Gastelum recommends finding a toothpaste flavor you’re excited to use; investing in an electric toothbrush (many of them include built-in timers so you know exactly how long to brush); and brushing with a friend, family member, or roommate.

“It helps build connections and also motivates you to make it a consistent habit,” he says.