Dear American women,

I’m embarrassed to be writing to you today. I’m doubly embarrassed because I’m not really talking to you. I’ve tried, honestly, to reach men. But because this article is about gender, no man will read it. Recently, I wrote a book called “The Unmade Bed: The Messy Truth About Men and Women in the 21st Century.” I’ve been interviewed about it maybe 20 or 30 times, and always — always — by women.

Men’s ignorance is a problem because the reality of gender is changing, viscerally, dramatically, and there are some things men need to know about. And they don’t know and they aren’t listening.

My hope is that the women reading this piece understand the ignorance of men and are willing to put it in front of some they care about. Younger men, preferably: sons or nephews or brothers or boyfriends or husbands or the local football team or whatever. What they need to know is not particularly complicated, though it will probably surprise most of them. The key points, the life-saving points, boil down to just three things:

1. Don’t take your friendships for granted. This may seem like a small point, but it isn’t. Growing up, for men, means growing out of their friendships. As boys mature into men, they shed their intimate relationships with each other. Girls don’t. And the suicide rate for men spikes exactly as they lose their friendships. Between the ages of 10 and 14, boys are twice as likely to commit suicide as girls. Between 15 and 19, it rises to four times. By 20 to 24, it’s five times.

Men are social animals, even though all male ideals tell them they should be alone. Traditional masculine ideals are lonely figures — cowboys, astronauts. But loneliness kills men. Divorced men are 10 times more likely to be depressed than married men. Divorced men have a mortality rate 250 percent higher than married men. Men have to make a conscious effort to be social. Otherwise, they die.

2. Misogyny makes you way less healthy. The evidence on mental health is unequivocal. In a recent study by the American Psychological Association involving 19,453 participants, researchers tested 11 traits associated with traditional masculinity. Almost all of them are bad for you. “Being a playboy” and holding “power over women” are the norms most closely associated with sexist attitudes, and the report is very clear about what happens to men who most value these concepts, stating that: “Conformity to masculine norms was significantly and unfavorably associated with mental health and psychological help seeking.” When you see some guy treating women like garbage, he’s not strong. He’s weak.

3. Take women’s jobs. You don’t really have a choice on this one. It’s very simple: Traditionally male jobs in industry are disappearing. Traditionally female jobs in the service sector are growing. Women take men’s jobs more and more. Men are not taking women’s jobs. The United States lost 5 million manufacturing jobs between 2000 and 2014. Thirteen of the 20 fastest-growing industries in America are in health care. Do the math.

Don’t abandon your friends. Don’t treat women like garbage. Don’t limit yourself to jobs that men used to do.

Two weeks after Trump was elected, a self-driving truck service delivered a shipment of Budweiser in Colorado. If you are a truck driver, start training to be a nurse now. If you are young, expand beyond the jobs you may have once considered. The definition of a man for generations has been a family provider. You won’t be able to provide if you don’t take women’s work.

That’s it. It’s just those three points: Don’t abandon your friends. Don’t treat women like garbage. Don’t limit yourself to jobs that men used to do.

This advice is not complicated. And knowing this information will make a huge difference in the personal health and well-being of any man who thinks about it for two minutes.

But getting men to think about their new reality for two minutes seems a nearly inhuman feat. Men are not used to thinking of themselves as belonging to a gender; women are. Because men will not face the new gender realities, they are suffering, and their suffering has consequences for everyone. Middle-aged white men are dying at unprecedented rates — from opioids, from booze, from suicide. According to the Case-Deaton report, the mortality rate of American men in the middle of their lives has risen 20 percent since 1999.

Let me sum up for you what they are really dying from: not facing reality.

Stephen Marche is a columnist for Esquire. His new book, “The Unmade Bed: The Messy Truth About Men and Women in the 21st Century,” is out now.