Dr. Trisha Pasricha said gut health is crucial for overall wellness. Support it with simple habits like eating fermented foods and taking a fiber supplement. Courtesy of Dr. Trisha Pasricha

A doctor said simple diet habits can help improve digestion and overall health in a few weeks.

Better gut health starts with eating more whole foods and fermented foods, and drinking less alcohol.

She also recommends a cheap supplement called psyllium husk that makes it easier to get more fiber.

Dr. Trisha Pasricha wants everyone to experience "poophoria," the joy of a healthy digestive system.

Your gut health is the key to improving your overall health and well-being, according to Pasricha's new book "You've Been Pooping All Wrong."

As a gastroenterologist and professor at Harvard Medical School, she works with patients on simple, everyday habits for gut health, and said you don't need expensive pre- or probiotic pills to see a difference.

"The gut health supplement industry is so loud in our feeds, it hijacks the…