When Sustain Natural launched in 2013, the idea for a sexual wellness brand was a nascent concept. “People laughed or were very uncomfortable with the idea of sexual wellness or period care when I started this company,” says co-founder and CEO Meika Hollender. “I was seen as a pariah.”

Though Sustain Natural’s products were not new — the company sells an assortment of lubricants, condoms, period cups and tampons — its positioning of sex or sex-related products as wellness was. Today, sexual wellness items are merchandised in Ulta Beauty stores nationwide (inside larger wellness sections) and Playboy magazine, a title once dedicated to the pursuits of male pleasure, is launching a sexual wellness line.

But sexual wellness is just one tangential segment of the larger wellness economy, which began gaining traction in 2008. Nowadays, clean beauty is wellness, CBD is wellness, pet care is wellness and, even, alcohol and funeral companies have a wellness bent.

“Wellness has become such a massive term and has massive reach,” says Beth McGroarty, vp of research at the Global Wellness Institute. “It was not a word you heard much about 10 years ago, and there is no coincidence that it took off when the first smartphone came out. Wellness began being talked about as a response to issues like stress, aging and loneliness that the medical industry did not curb. A consumer industry was born.”

While wellness was once associated with affluence and elitism in the vein of Gwyneth Paltrow’s Goop, the category’s expansion has fueled the market to be valued at $4.2 trillion presently. For its part, the Global Wellness Institute only tracks 10 sectors within the larger landscape including healthy eating, the spa economy, beauty, preventative medicine and workplace wellness, but McGroarty admits that many companies are increasingly rebranding to have a wellness angle.

“Because of the success of the market, traditional segments are breaking down,” she says. “The fashion industry has an argument when they are trying to make sustainable clothes a thing and sobriety has been repositioned in a way that a no-sugar diet might have in the past.”

That stretchiness of wellness is to be expected, says Stephen Sokoler, founder and CEO of mediation app Journey Live. “The generations before ours did not think about their well-being, and now there are so many ways to become mentally, physically and emotionally fit and happy,” he says. Journey Live, which offers live meditation classes in app form, was born after Sokoler led workplace wellness sessions at Warby Parker and Facebook.

Still, the word’s vagueness can be problematic, especially when products like a single-use sheet mask for Self Care Sundays can negatively affect an individual or, in a larger scope, the environment and society as a whole. “We’ve seen pharmaceuticals pitched as wellness, making it seem like that decision is as easy or risk-free as to pick up a mascara at Sephora or take a workout class,” says Tina Bou-Saba, founder of CXT Investments. “The trend of wellness continues to grow, but as regulations on CBD or supplements begin, that will affect investors and eventually the end customer.”

McGroarty agrees. “Things like Flatbelly Tea can have harmful effects, and that might cause a need for a wellness call-out, like an Estée Laundry in beauty or Diet Prada in fashion,” she says. “But one of the newest wellness trends today is in crystals, shamans, astrology and tarot cards; belief culture has very much become a part of wellness. No one is going to die if they do pilates or try a plant-based diet, so if the belief that it makes people feel good continues, the wellness market and what it means won’t stop anytime soon.”