PHILADELPHIA — A debilitating digestive illness led to the launch of Halfday Tonics, a brand of canned tea beverages featuring prebiotic fiber. Founders Kayvon Jahanbakhsh and Michael Lombardo began developing the concept as college students several years ago following a severe bout of ulcerative colitis that hospitalized Mr. Jahanbakhsh for three months and sank his swim career.

Halfday was inspired by the pair’s favorite summertime refreshment, bottled or canned tea from such brands as Snapple, Arizona and Brisk. Mr. Jahanbakhsh eliminated these drinks from his diet to avoid flare-ups of his disease, which is triggered by high sugar intake, he said. The addition of inulin to homemade batches of iced tea aided his recovery and sparked the idea for the business.

“As I started to get better and better, I realized there’s a need for this,” he said.

An overwhelming majority of Americans fail to consume the recommended amount of dietary fiber per day. Many brands marketing digestive wellness typically target older shoppers, Mr. Jahanbakhsh said, citing Activia and Metamucil as examples. Halfday was designed to appeal to Generation Z and millennials, who are more likely to seek lower-sugar beverages, Mr. Lombardo said.

The products are formulated with organic ingredients, including green or black tea extract, Jerusalem artichoke inulin, agave inulin, apple juice concentrate and lemon juice concentrate, plus stevia leaf extract. Varieties include peach green tea, lemon black tea and green tea with honey and ginseng. A seasonal flavor, cranberry black tea, is set to debut in November.

“There really hasn’t been iced tea innovation since Honest in the ‘90s and early 2000s,” Mr. Jahanbakhsh said. “We really liked iced teas as kids, even going into our adult years, but obviously over the age of 18, it’s pretty difficult to drink 40 grams of sugar in a sitting and feel good after.”

A serving of Halfday tea contains 8 grams of fiber and 3 to 4 grams of sugar. (A 12-oz serving of Snapple peach tea, by comparison, has 30 grams of sugar). Halfday products are available on the brand’s website,, as well as at select specialty and natural foods stores and online grocers including Thrive Market and Misfits Market.

Mr. Jahanbakhsh and Mr. Lombardo introduced Halfday this past May following multiple product iterations, including cold-brewed and carbonated varieties under the name Topos. The new branding and current recipes were created during the founders’ participation in the BeyondSKU consumer products accelerator program late last year.

“At that time, we were still trying to figure out, do we want to be a sparkling tea? A soda alternative? What are we?” Mr. Jahanbakhsh said. “I remember Mike and I just sitting and ideating for hours and hours.”

The startup recently closed a pre-seed funding round, raising $750,000 from Electric Feel Ventures, Over Easy Ventures, Distributors Fund and angel investors including Halo Top Creamery co-founder Doug Bouton. The founders planned to use the proceeds to expand retail distribution.

“We get reviews from people who always drank Brisk or Arizona, and they’re able to switch without making that sacrifice, which is really cool,” said Mr. Jahanbakhsh, who described Halfday as “Snapple 2.0.” “They can basically reduce their sugar consumption by 80% to 90% and still get that full satisfaction of a classic iced tea and, on top of that, the digestive health benefits.”