Dr. Ruth's Best Sex Tips Including Why Fifty Shades of Grey Can Help in Bed

“There’s no such things as crazy questions,” says Dr. Ruth Westheimer, the 90-year-old sex therapist who’s heard it all when it comes to sex.

Westheimer, who’s call-in show, Sexually Speaking, on WYNY public radio, became a phenomenon in the ’80s, stresses sexual responsibility — and satisfaction. Her remarkable story is now the subject of a powerful new documentary Ask Dr. Ruth, in theaters May 3 and on Hulu on June 1.

In this week’s PEOPLE issue, she shares a few of the top sex tips she’s learned along the way.

No. 1. Seduce with Words

“Put down the screen and get to know each other,” she advises. “Good sex is not just about what’s between the waist and the knees. It’s mainly in the brain. Laughter is also an important ingredient because it frees up the mind.”

Ask Dr. Ruth | Hulu
Ask Dr. Ruth | Hulu

No 2. Fantasy Is Fun

“Use fantasy because it permits variety and helps couples avoid boredom. But don’t put your next door neighbor in your fantasy because that could become a reality! The grass is not always greener on the other lawn.”

No. 3. Read a Sexy Book

“I read all three volumes of Fifty Shades of Grey. Erotic literature doesn’t have to be great literature. Use it to spin off your own ideas. If it serves to help put your worries aside and put you in the mood, use it.”

No. 4. Don’t Forget Afterplay

“A quickie may be enjoyable sometimes but a good sexual experience needs time — for arousal as well as for hugging and kissing after sex. Afterplay and caressing are part of the arousal phase for the next encounter.”

Westheimer developed her speciality in sex therapy after studying psychology, and obtaining her masters in sociology and then her doctorate. While working as director of research at Planned Parenthood, she had an epiphany of sorts.

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After her first day on the job, she says, “I told Fred [third husband Fred Westheimer], ‘Something is wrong with these people, all they talk about is sex.’ And 24 hours later, I said, ‘Oops, what an interesting subject matter.'”

Some five decades later, she still feels the same way: “It’s still the case,” she says. “Exactly.”

For more on Dr. Ruth and her extraordinary life, pick up a copy of this week’s PEOPLE.