Many surf the web to learn more about their health. But what subject matters are people researching most?

» RELATED: How the keto diet can keep your brain healthy and young

Google did some digging to find out. By gathering data, based on search terms, from January to mid-December, the search engine site determined the top 10 health-related questions of 2018.

The keto diet was a hot topic. It was the No. 1 health-related query searched for on Google this year. The low-carb, high-fat, moderate-protein diet aims to put the body in ketosis, which is the process of breaking down fat into ketones to create energy.

People were also curious about ALS or amyotrophic lateral sclerosis, which came in at No. 2 on the list. It’s a progressive nervous system disease that attacks nerve cells in your brain and spinal cord.

Endometriosis was the third most-searched topic. The painful disorder occurs when the tissues that normally line the uterus grows outside of the uterus.

Want to know about the other questions on the list? Here are the top 10 searched for items on Google in 2018.

1. What is the keto diet?

2. What is ALS disease?

3. What is endometriosis?

4. How long does weed stay in your urine?

5. How long does the flu last?

6. How long is the flu contagious?

7. When does implantation bleeding occur?

8. Why am I always tired?

9. What does heartburn feel like?

10. What causes high blood pressure?

» RELATED: More people in the US Googled Stacey Abrams than any other politician in 2018