This article appears to be reliable because while it doesn't have an author, it was published recently (January 2022), it has no typos, and it is from Harvard Medical School, a highly prestigious and respected university. The claim that excessive sugar intake can lead to serious health issues is backed up almost entirely by a study done through Harvard. There are several quotes from Dr. Frank Hu, a professor of nutrition who worked on the study. After further research, I found that he has worked on numerous published health studies and received ten awards for his work within the medical research field. Here is Dr. Hu's profile on the Harvard website.
Furthermore, I was able to find the study itself, which was published in 2014 by Jama International Medicine (Jamanetwork.com). Statistics between the article and this study matched, and Dr. Hu is listed as a collaborator. The study's conclusion states, "Our findings indicate that most US adults consume more added sugar than is recommended for a healthy diet. A higher percentage of calories from added sugar is associated with significantly increased risk of CVD mortality. In addition, regular consumption of sugar-sweetened beverages is associated with elevated CVD mortality. Our results support current recommendations to limit the intake of calories from added sugars in US diets." This supports the article's claim that consuming too much sugar poses health risks.
Additionally, I looked up "sugar health risks" on Google and found many other articles covering the topic, including a study by the National Library of Medicine which states that, "very little scientific evidence exists that indicates a benefit of added dietary sugars; however, an overwhelming and growing body of evidence highlights the negative effects of excessive or prolonged sugar intake." An article by The Centers for Disease Control and Prevention also corroborated the claim. Therefore, considering the high credibility of the article, it's referenced study, and outside sources, it's clear that this claim is true.