"I always fasted on Yom Kippur," he recalls. "I still worked on the movie sets, but I fasted. And let me tell you, it's not easy making love to Lana Turner on an empty stomach."
Besides bearing up under this ordeal, the nonagenarian has survived 87 movies, countless one-night stands with filmdom's most beautiful women, a helicopter crash, a stroke and two bar mitzvahs.
He's not done yet, not by a long shot. Just out is his ninth book, "Let's Face It: 90 Years of Living, Loving and Learning." It is a mix of reminiscences, anecdotes, tributes to Hollywood luminaries now faded or gone, a critique of America's present leadership and somber thoughts on the drug-induced suicide of Eric, the youngest of his four sons.
As in his previous works -- three memoirs, three novels and two children's books on biblical and Holocaust themes -- Douglas writes with the artlessness of a man talking about the incidents and reflections of an interesting life, whose casual conversation has been surreptitiously taped and transcribed.
When I mention this appraisal to Douglas, he seems pleased. "I am glad to hear you say that, because I don't want to be like a writer. I want to write impulsively," he comments.
It is almost impossible to recall the 1950s, '60s and '70s without remembering a Douglas movie. In the '50s alone, he starred in 23 films, receiving Oscar nominations for "The Bad and the Beautiful" and "Lust for Life" (as Vincent van Gogh). These were bracketed by his 1949 breakthrough role as a cynical boxer in "Champion" (his first Oscar nomination) and perhaps his best-known movie, "Spartacus," in 1960.
Douglas produced and played the title role as the leader of a slave revolt against ancient Rome in "Spartacus." He himself received no Academy Award honors but earned even higher distinction for moral courage by breaking the McCarthy-era blacklist of artists suspected of communist leanings -- in this case, openly employing screenwriter Dalton Trumbo.
Now Douglas, pronouncing each word slowly, carefully and with a slight slur after his stroke forced him to re-learn the language ("For a guy who can't talk, I sure talk a lot," he jokes), has reached a new stage in his life.
Once known as one of Hollywood's most self-centered denizens, in a town notorious for supersized egos, Douglas is now looking beyond himself. He is exhorting the Internet generation to practice tikkun olam (repairing the world) through social action and respect for human rights.
Douglas knows where to reach his target audience -- not in the movie theaters but on MySpace and YouTube. There he urges the young viewers "to rebel, to speak up, vote and care about people.... You are the group facing many problems: abject poverty, global warming, AIDS and suicide bombers ... we have done very little to solve these problems. Now we leave it to you. You have to fix it, because the situation is intolerable."
Douglas' own childhood might well seem intolerable to most young people in Britain or America today. The Nordic-looking hero, who vanquished hordes of Vikings and Romans on the screen, began life as Issur Danielovitch in the small town of Amsterdam in upstate New York.
His parents were poor, illiterate immigrants from Russia, and his father made a precarious living as a peddler. In his first memoir, "The Ragman's Son," Kirk recalls, with undiminished pain, growing up with a loveless father who was unresponsive to his son and six daughters.
To compensate, he makes it a point to show emotion and affection toward his own children and grandchildren. "When we meet," he says, "we embrace and kiss each other on the mouth, Russian style."
Douglas has always been aware of his Jewishness. When he was 12, the Sons of Israel congregation in his hometown offered to send him to a yeshiva to become a rabbi. Young Kirk declined, informing his would-be benefactors that he would become an actor.
But for most of his life, he has been an indifferent Jew, at best. At one point in college, though a popular student body president and champion wrestler, he tried to pass himself off as a half-Jew.
He dates his return to Jewish observance and full identification to a collision between his helicopter and a light stunt plane, in which two young men died while he survived. The crash in 1991 compressed his spine by three inches, and while lying in a hospital bed with excruciating back pains, he started pondering the meaning of his survival and his life.
"I came to believe that I was spared because I had not yet come to terms with my Judaism, that I had never come to grips with what it means to be Jewish," Douglas reflects.
In his mid-70s, Douglas embarked on an intensive regime of Torah studies with two young Orthodox rabbis and found an immediate relevance to his profession.
"The Torah is the greatest screenplay ever written," he observes. "It has passion, incest, murder, adultery, really everything."
These days, Douglas has a weekly study session with Rabbi David Wolpe of Sinai Temple, but he is hardly an unquestioning pupil. Sitting in his office in Beverly Hills, relatively modest as is his art-filled house where we had met on previous occasions, Douglas poses a few questions.
"Why was God so talkative in biblical times but doesn't talk to us now? We Jews are supposed to be smart, so why was Samson so dumb as to let Delilah cut off his hair?"
Wolpe officiated at Douglas' second bar mitzvah, at which time the 83-year-old celebrant informed the assembled Hollywood glitterati, "Today, I am a man."
On the present state of his Jewishness, Douglas ruminates, "I think of myself as a secular Jew, but I have great admiration for Chasidic Jews who preserve the old laws. I attend High Holy Days services -- every man should have a day of atonement -- and I light candles in my home every Shabbat. I don't keep kosher, but it would be very difficult for me to go into a restaurant and order pork."The religious makeup of the Douglas family reflects the growing American pattern, in which every member determines his or her own identity.
Neither Douglas' first wife, actress Diana Dill, nor his second wife, the former Anne Buydens, were Jewish. So according to halacha, neither sons Michael and Joel from the first marriage nor Peter from the second marriage are Jewish or were raised as such.
"I have never followed the commandment to teach your children," Douglas says.... "But my sons always knew I was a Jew, even way before I studied Torah. But I have found that the last few years that I have studied Judaism and after taking pride in being a Jew, that has impressed my sons.... Michael, I think, is very Jewish. He feels as a Jew, and he is ready to help Jewish causes."
The balance shifted further on Douglases' 50th wedding anniversary in 2004, when Anne announced that she had converted to Judaism. "Kirk has been married to two shiksas, and it's about time he married a nice Jewish girl," she explained.
The couple repeated their wedding vows at the star-studded anniversary celebration, quite a change from the quickie ceremony at a Las Vegas wedding chapel the first time around.
At that time, Anne, born in Germany and raised in Belgium, was still new to the country and the language, after meeting Kirk in Paris. When asked to recite the wedding vow, she solemnly intoned, "I take thee, Kirk, as my awful wedded husband."
"I had never heard the word 'lawful,' and when everybody laughed, I nearly cried," she explained later.
Their union has now lasted for 53 years, a millennium by Hollywood standards, overcoming Douglas' continuing philandering in the early years, his long absences as an actor, her breast cancer, his stroke and the devastating suicide of their youngest son.
What did Anne have to attract a man who, after all, counted Joan Crawford, Gene Tierney, Rita Hayworth, Marlene Dietrich and battalions of lesser-known beauties among his trophies?
"Her vicious sense of humor," according to Douglas. An early demonstration of this trait was the surprise birthday party Anne threw for him in Paris before their marriage.
Somehow, Anne managed to track everyone in a long procession of girls Kirk had escorted and/or bedded in the months that he was shooting a movie in the French capital. When the unsuspecting Douglas entered, he was confronted by a long receiving line consisting of all his previous conquests.
By now, however, Douglas says with conviction, "My love for Anne is growing deeper all the time ... when I think of all she had to go through."
One chapter in "Let's Face It" is titled, "Romance Begins at Eighty," and in it, Douglas lists all the little surprises and romantic gestures that will keep the flame burning.
In answer to my question on the formula for an enduring marriage, Douglas goes a little deeper. "Be understanding of each other, but don't focus only on your relationship," he says. "Reach out and be concerned with the world around you."
Both he and Anne express their concern through public service and support of numerous charities, many focusing on children. "We have underwritten 360 public playgrounds, including four in Israel for both Jewish and Arab kids, and are aiming for a total of 400," he says.
Separately or together, the Douglases have also endowed centers for homeless women and for AIDS and Alzheimer's research and support a number of Israeli medical and educational institutions. A theater facing Jerusalem's Western Wall, which screens films on Jewish heritage for visitors; a Los Angeles theater for experimental plays; and a Los Angeles high school all bear the Douglas name.
Douglas has been an ardent supporter of Israel since his first stay there in 1953 to film "The Juggler," returning in later years for "Cast a Giant Shadow" and "Remembrance of Love."
Recent political scandals and dissentions in Israel have not discouraged him. "Look," he says, "when I first went to Israel, the rationing was so bad a person could buy only one egg a month. They've fought six wars and at the same time have created one of the foremost technology industries in the world.
"I have known Moshe Dayan, Yitzhak Rabin, Ariel Sharon and Ehud Olmert. You can't help but admire the country and its people."
Douglas reaffirmed his pride in Israel in "Let's Face It" by reprinting a letter he wrote to President Jimmy Carter after reading the latter's book, "Palestine, Peace Not Apartheid."
The relationship between the two men goes back to 1981, when Carter conferred the Presidential Medal of Freedom, America's highest civilian award, on Douglas for his public services abroad on behalf of the United States.
Since then, they have remained friends and have visited each other's homes. Nevertheless, Douglas pulled no punches in criticizing Carter directly for his skewed facts on the Middle East and his anti-Israel position.
As a secretary enters the room to announce that the interview has already run beyond the allotted one hour, Douglas squeezes in one more thought on Jewish identity.
"I'm often told, 'You don't look Jewish,'" he says. "Is that a compliment or an insult? I don't know."