Time for some tough talk about the male waistline — specifically what’s right above it… and what’s right below, because the two are more closely linked than you might think.

Fatty tissue contains an enzyme called aromatase, which transforms your manly testosterone into a form of the not-so-manly hormone estrogen. That doesn’t just sound like bad news for male sexual health… it IS bad news, and a new analysis out of France makes my point perfectly.

Researchers looked at 14 studies that compared sperm counts in normal weight, overweight, and obese men and, not at all surprisingly, found that obese men were 42 percent more likely to have low sperm counts.

Even worse, the obese guys were 81 percent more likely to produce no sperm at all.

You don’t have to be obese to lose your manpower, either — because even overweight (not obese) men were having trouble producing. They were 11 percent more likely to have low sperm counts and 39 percent more likely to have no sperm at all than normal-weight men, according to the study in the Archives of Internal Medicine.

It’s not just low counts. Other studies have found that obese men have lower sperm quality, too, including low concentration and low motility (that’s the ability to move towards the egg for fertilization).

On the other hand, many overweight and obese men never realize they have any of these sperm problems in the first place because of one of the other effects of those extra pounds: erectile dysfunction.

OK, I can practically sense some of you squirming as you read this. No guy suffering from sexual dysfunction or low sperm counts wants to talk about it, and I’ve had my share of patients come in and beat around the bush or ask about a “friend.”

I get it — so let me save you from that awkward conversation. If you’re overweight and suffering from any form of sexual dysfunction, drop the pounds.

If weight isn’t the cause of your problems, then don’t be shy. Have that conversation — because there could be something else going on that needs attention such as low testosterone or impaired circulation.

And don’t worry. Your doctor’s heard it all before.

Empty calories aren’t just bad for your belly. They can be downright ruinous for your brain — and the latest research shows again how people who eat the most have the highest risk of memory problems.

That means watching what you eat now could be the simplest way to avoid dementia later on.

Researchers divided some 1,200 seniors between 70 and 89 years old into three categories based on how many calories they ate each day: a third consumed between 600 and 1,526 calories a day, a third chowed down on between 1,526 and 2,143, and the final third ate between 2,143 and 6,000 calories a day.

Those in that last group had double the risk of mild cognitive impairment compared to the rest of the eaters in the study, even after adjusting for other risk factors like age, education and health history.

But if you’ve noticed that the last category was rather broad, you’re not alone.

It seems to me there’s a huge difference between someone who eats 2,200 calories a day — which can be healthy, depending on how you get those calories — and someone who gorges on 6,000 calories a day… which isn’t healthy no matter what you eat.

Yet in this study, they’re both lumped into the same group. In addition, the study was based on food frequency questionnaires — so those numbers are guesstimates at best.

But I’m not ready to write this study off yet, either, because there’s a clear link between diet and dementia — and other studies have also found that people who weigh the most have the highest risk of the condition.

One study found that women with the biggest waistlines in middle age had double the risk of dementia in old age. Another found that men and women alike with the highest levels of abdominal fat have more than triple the risk of dementia of those with the least.

And yet another study last year found that overweight people see significant improvements in both memory and concentration when they lose weight.

But if that’s not enough of a reason to drop the extra pounds, consider all the other risks that accompany obesity: heart disease, diabetes, cancer, depression and — of course — an early demise.

If you can avoid all that by eating a little better, I say go for it.

At least we’re not getting fatter.

The newest obesity numbers are in and, well, this is what passes for victory these days: Americans have had roughly the same rate of obesity for much of the past decade, with a little more than a third of us in need of plus-size clothing.

That includes 17 percent of children, and represents almost no change since 2003.

But is this really progress? We’ve got 78 million obese adults and 12.5 million obese kids, according to these new numbers from the CDC — and tens of millions more are already overweight and ready to join their ranks.

It’s still a massive public health crisis — but every crisis is an opportunity, and this is one opportunity the drug industry can’t wait to sink its fangs into.

Along with a host of bad weight-loss meds awaiting approval, Big Pharma is trying to push meds already on the market for other conditions — including diabetes drugs.

One new study has researchers practically giddy, claiming it shows that the new generation of diabetes meds — GLP-1 agonists like Byetta and Bydureon — can help obese non-diabetics lose weight.

They claim these drugs helped some people lose 20 pounds — and that in practice, they’ve seen patients drop up to 50 pounds while taking them.

But just like scammy fad diet commercials, this one should come with a bold-face warning: RESULTS NOT TYPICAL.

The study in BMJ didn’t find that most people lost 50 pounds. It didn’t even find that they lost 20 pounds — or anything close to it.

In fact, the average weight loss was just 6.4 pounds — and who knows if that’s even permanent. You might have to take the meds forever to keep that weight off.

I don’t know about you, but I don’t think that’s worth getting giddy over — especially when you consider the side effects of these meds: nausea, vomiting, diarrhea and more.

Of course you’ll lose some weight if you can’t keep your food down — and along with those stomach-turning side effects, GLP-1 agonists have been linked to pancreatitis as well as pancreatic and thyroid cancer.

Who wants to risk all that to lose 6.4 pounds over 20 weeks?

Forget meds. There’s a much safer way to lose a lot more weight, and you don’t need to swallow a single pill: Go sugar-free and low in carbs while eating fatty fish, farm-fresh chicken and grass-fed meats.

It might take a little discipline — but it’s still a heck of a lot easier than taking diabetes meds for the rest of your life.

If you want to weigh less… eat more often.

That might sound counterintuitive, but some of the most successful dieters around are the ones who make sure they have all three meals each day — or even more.

I even know some slim and trim people who eat five or six small meals a day. It’s like they’re always eating — yet they never gain any weight.

A new study confirms that these people aren’t just blessed with a magical metabolism — just good habits. Because as it turns out, overweight and obese people actually eat less frequently than people who keep slim and trim.

Researchers used data from two studies on eating habits: One looked at how much — and how often — obese and overweight people ate, while the other looked at the habits of people who had normal BMIs for at least five years.

Roughly half of the people in that second study were once overweight or obese themselves, and had to lose at least 30 pounds to get there.

Regardless of whether they were once fat or always thin, these normal-weight people had a few things in common: First, they were more likely to eat three meals a day and two snacks than the overweight and obese, who actually ate less frequently (including, believe it or not, fewer snacks).

Second, the thin people consumed up to 200 fewer total calories each day despite their more frequent feedings, according to the study in the Journal of the American Dietetic Association.

And third, the people who kept the weight off were more likely to get more movement — a lot more movement. In fact, the researchers say they burned up to 2,200 calories per week more than the overweight and obese.

If you’re overweight and hate the idea of joining a gym, don’t worry. The good news is these people weren’t iron-pumping fitness fiends. They weren’t even treadmill junkies.

They just walked an average of 60 minutes a day, every day — something just about anyone can do if they commit to it.

Naturally, it doesn’t matter how often you eat if you eat all the wrong things — three meals a day at McDonald’s will still leave you bloated and sick, and let’s not even think about two daily snacks of chips and ice cream.

So eat more often — just make sure you eat better, too. And if you commit to a healthy diet low in carbohydrates and rich in healthy fats and fresh vegetables, you won’t even have to count calories.

Just eat until you’re full, and your body will take care of the rest.