Last year, American novelist Joyce Maynard faced a harsh realization: Her habit of reaching for a glass of wine whenever she felt stressed had crossed the line into an addiction.

“It kind of crept up on me,” said Maynard, 63, whose novel about a single mother with a wine dependence, “Under the Influence,” came out in paperback in November. “The way I was drinking is the way a lot of women drink and don’t see it as any kind of problem. And for a lot of them, it may not be a problem. It wasn’t the quantity; it was the space wine occupied in my life. I could tell it was occupying an unhealthy one. I was using it increasingly as a comfort and a reliever of stress. I would say, ‘I’m not going to drink,’ and then I would.”

Maynard is part of an increasing cohort of women who have been drinking (or abusing) alcohol more than women did only a few decades ago, and in patterns increasingly similar to men’s. Health officials are watching the situation with concern, and some addiction specialists are making comparisons to other dependencies to which women may be more vulnerable, such as food addictions.

Recent research makes the pattern with women and alcohol clear. Analyzing 68 alcohol-use studies from around the world dating to the mid-1900s, Australian researchers found a remarkably steady “gender convergence.” Their review and analysis, published in October, showed that men born in the early 20th century were more than twice as likely as women to drink and three times as likely to have an alcohol problem — but for those born closer to the end of the century, those ratios were 1.1 and 1.2 to 1, respectively. In other words, the difference between male and female drinking had all but disappeared.

The study reinforced earlier, smaller studies, including one in September 2015 that used data from the National Survey on Drug Use and Health to demonstrate how the U.S. gender gap in drinking had narrowed from 2002 to 2012.

Author Joyce Maynard, shown here in 2013, said she began drinking more wine when her late husband was diagnosed with pancreatic cancer. (Vince Bucci/Invision/AP)

The authors of these studies don’t explain why this is happening. But clinicians and other professionals have opinions.

“It’s presumably [caused by] all the factors associated with women having a different culture than they did 100 years ago,” George Koob, the director of the National Institute on Alcohol Abuse and Alcoholism, said in an interview. “Instead of being at home, they’re in society, and drinking is part of business and social gatherings. Another issue that’s relevant, there has been a decline in underage drinking in men that is not happening with women.”

He added that “women report depression and anxiety twice as much as men, and . . . depression and anxiety are often comorbid with addictions.” Furthermore, among women who drink, “alcohol use tends to escalate more quickly than with men” — what doctors call a “telescoping effect.”

The main problem with women drinking like men is that they don’t have the same physiology as men. Women are more susceptible to alcohol’s effects, largely because they have lower body mass, and in particular less water to disperse the alcohol through their bodies. “Therefore, a woman’s brain and other organs are exposed to more alcohol and to more of the toxic byproducts that result when the body breaks down and eliminates alcohol,” notes the NIAAA, part of the National Institutes of Health.

In the short term, alcohol is quicker to affect women’s ability to function. Long term, women who drink are more likely than men who drink to develop breast cancer, alcoholic hepatitis and certain heart problems.

Food addiction, in contrast, can lead to weight gain and its well-documented health effects, including higher risks of diabetes and heart disease. Food addiction is still an emerging field of research, but the relatively few studies so far that sort data by gender show that women appear to be more vulnerable here, too. Of the 652 adults who participated in a 2013 Canadian study, more than twice as many women as men met the Yale Food Addiction Scale criteria for food addiction. And a 2016 U.S. study designed to test an update of the Yale Scale found that “gender was significantly associated with ­addictive-like eating symptoms with women, on average, reporting a higher number of symptoms” than men.

Ashley Gearhardt, the lead developer of the Yale Food Addiction Scale, noted that women might be more vulnerable to addictive eating patterns because of “so many pressures” in their lives — “pressures in the workplace, pressures regarding child care.”

And there are other social pressures. “Women, more than men, are held to unattainable beauty ideals against the backdrop of a toxic food environment,” she said. “This can increase the likelihood that women will bounce back and forth between the extremes of intense dietary restriction and binge eating.”

No matter where stresses come from, experts agree that they can push a merely unhealthy food or drinking habit into an addiction. But how does one tell when a fondness for a snack or nightly cocktail starts becoming an ­issue?

“It stops being about how much you like it,” Gearhardt said. “People say, ‘I don’t even like it anymore. I want it or crave it.’ You start to feel you can’t control it. Some people say that they’re ‘addicted to chocolate.’ You can like chocolate or look forward to it or have it as a special treat. That’s not an indication of a concern, normally — but it is when you experience such intense cravings that you feel you can’t manage, when it impacts your life.”

Recently, scientists have been fine-tuning the diagnostic tools for what constitutes a substance-use problem, making it easier for people to recognize when their ritual becomes risk.

Notably, when the American Psychiatric Association updated the Diagnostic and Statistical Manual of Mental Disorders in 2013, it changed the way it categorized drug and alcohol issues: Instead of dividing them into two categories — abuse and dependence — the new DSM-5 established a spectrum of “substance use disorders,” based on 11 questions about symptoms. The questions emphasize psychological issues, such as a new question about cravings: “In the past year, have you wanted a drink so badly you couldn’t think of anything else?” (The list can be found online, including at the NIAAA’s website, niaaa.nih.gov.)

According to the manual, the presence of at least two of the 11 symptoms indicates a substance or alcohol disorder, and six or more symptoms mean it’s severe.

Echoing that update, ­Gearhardt and her colleagues revised their Yale Food Addiction Scale in February 2016. The ­original 2009 scale, considered the yardstick for measuring food dependence, included 25 questions about a person’s relationship to food, but the Yale Scale 2.0 has 35 ­more-specific questions, which pay attention to psychological ­symptoms, and food’s effects on ­personal life. (The questionnaire is downloadable at ­fastlab.psych.lsa.umich.edu/yale-food-addiction-scale/ .)

As in the DSM-5, cravings were added to the Yale Scale — “I had such strong urges to eat certain foods that I couldn’t think of anything else.” Gearhardt, who directs the Food and Addiction Science and Treatment Lab at the University of Michigan, said these cravings go well beyond most people’s everyday hunger — like having to get up and leave a business meeting to satisfy a desire for a specific treat.

“Other things we’ve seen clinically, someone may go from grocery store to grocery store to buy food to binge,” Gearhardt said. “They don’t go to just one place to buy it, because of the shame and embarrassment. Or they may have a social engagement but they lose control and cancel so they can stay home and binge. People lose control and really feel not well as a result.”

A few bouts of excessive drinking or eating may not indicate a severe problem: A Centers for Disease Control and Prevention fact sheet notes that “approximately 12 percent of adult women report binge drinking three times a month” but goes on to say that “most (90 percent) people who binge drink are not alcoholics or alcohol dependent.”

But both Koob and Gearhardt stressed that when a substance negatively affects someone’s life, or they answer positively to criteria on the DSM or Yale Scale, they should seek further help.

“One of the really good things about the DSM-5,” Koob said, “is that it emphasizes that you don’t have to be what we used to call an ‘alcoholic’ to have a problem. Now you can try to seek out a counselor, seek out a family physician, seek out a religious person in your community so that problems with alcohol can be stopped before they progress. It may make it a little clearer that a problem with alcohol is a spectrum of intensity, and is not always the guy you see out on the street. And the guy on the street is often the exception. Alcohol use disorders pervade our society.”

Gearhardt said, regarding food addiction, “We’ve treated people clinically who tried to manage for 20 years on their own, trying any diet they could get their hands on, but they didn’t see a therapist or psychologist, and they ran out of options.”

In Maynard’s case, her longtime enjoyment of wine kicked into high gear after her late husband, Jim, was diagnosed with pancreatic cancer in November 2014. During the worst of his illness, she says, she drank every night, sometimes half a bottle. After several failed attempts to quit in 2015, she decided she had to quit cold turkey in January 2016. A month later, she wrote a widely read online essay about her case.

Since then, she said, women have reached out to her about their addictions.

“So many women experience this,” she said. “We live with an enormous amount of stress. Reaching for a bottle of wine is one of the easiest, quickest ways to take the edge off.”

Today, Maynard is back to drinking, but in moderation; she says she always intended to drink again when she believed she could manage it. However, she has new rules: She will not drink every night, and never alone. She rarely has more than one drink. She attends Al-Anon meetings, organized for families of problem drinkers, as her late father was an alcoholic.

“I love to cook. I love wine with good food,” Maynard said. “There are times I wish that I could have more and know I cannot.”

She added: “I would say I had an addiction” — then, correcting herself — “I have an addiction that I’m always aware of. There may be people who will hear this or read this and say: ‘She’s kidding herself. She’s an alcoholic. She needs to not drink.’

“If I get to the point where I can’t maintain it, it will tell me the problem is too severe.”