Everybody in New York is opinionated. Everybody in New York is dieting. Everybody in New York is different.

All New York argues about something. Young ladies grouse about our heavy-duty pollution. Old broads enthuse: “Yeah, but the grime settles on our faces and fills in the cracks, and we look better.”

Some like the ritzy East Side, some the juicy West Side. One picks elegant white tablecloth fine dining uptown; another wants a sidewalk café downtown, where the noise level wins you a hearing aid.

New York. Chinese and Portuguese, Spanish and Danish, Indian and Puerto Rican, from Guatemala, from Indonesia. Franks off a street cart. Kobe steak for $250. Rich, poor. College, no college. Bums and CEOs.

Can’t even get agreement on a cup of coffee — latte, espresso, capuccino, American, Turkish, French café au lait, light, black, regular, strong, decaf, cinnamon, no cinnamon, skim milk, whole milk, fake milk, soy milk, almond milk, powdered milk, evaporated milk, vanilla flavored milk, cream, half and half, no sugar, real sugar, fake sugar, granulated sugar, lump sugar, brown sugar, two sugars, perk, instant, drip, fresh ground, a cup, a mug, a pot, iced, hot, luke, Maxwell House, Chock Full O’ Nuts, with a bagel, to go, to drink here.

Invite a group for dinner, and it’s easier to entertain Syrians with Israelis.

Kosher people refuse invitations on Friday, their night to light candles. Newly observant Jews include Chelsea Clinton, married to Mr. Mezvinsky, and Ivanka Trump, married to Mr. Kushner.

OK, but similar friends have invited me to Chinese restaurants. About spare ribs I’m not sure, but Chan Gow’s Peking Duck is Glatt kosher? And they frequent French joints. So do frogs legs and charcuterie get rabbinical blessing? On the road they’ve made pit stops in McDonald’s. Fine, but kashrut burgers for the Orthodox?

There are vegetarians like Paul McCartney and daughter Stella, who doesn’t sell leather or wear it. To them a lucullan repast is sautéed daffodils topped with bean paste and leg of tofu with a side of granola — hold the meat sauce. Alfalfa brings paroxysms of joy. Mushrooms, an orgasm.

I had a dinner party. One couple never mentioned they were vegans. For my high-class guest list of 14, the table was set with Ming dishes. Tiffany vases. Gold-plated cutlery. Irish lace cloth. So classy that I myself clashed with it.

Everyone was told 8 p.m. The couple, arriving 8:10, announced they’re vegans. No fish, no meat, no dairy, no poultry. No eggs, cheese, milk, butter, honey. Fruits and nuts. Seeds. Grains. Beans. Legumes.

Great. Shrimp was first course. Small chicken pot-pie second. Steak main dish. Home-made ice cream. Nothing could they eat. Nothing.

While guests milled about, the whole household began rushing around. Opened a can of soup, thawed frozen vegetables, invaded a box of stale cookies, fast boiled spaghetti, plucked out hard-boiled egg topping on the salad. What a mess. Ming isn’t thrown in a dishwasher so without time to handwash and with the sink full, on this House Beautiful table, we shoved Christmastime red and green paper plates. So harmonious on an all blue and white Chinese table.

Another time, I ended up with diabetics. That was manageable. You take away the sweets and sugars.

We’ve already learned that with cholesterol watchers it’s no fat, no sauce, no fried, no creamy buttery mashed potatoes, and lose the coconut cake.

High-blood-pressure types can’t have salt or they swell up. Low-blood- pressure types need lots of salt or they faint. I’ve fed both at the same meal where, come Passover, a couple made me replace silverware with paper knives and forks. Their dietary laws allowed one set for meat, one dairy and never the twain shall meet. And, trust me, their matzos did not work with our curry.

There’s the anorexics. An acquaintance who eats leaves sent me her snack specialty. Thin thin thin Danish wafers you can practically see through. Slather tuna salad, and the mayo dribbles through. She guaranteed they’re free of flavoring, chemicals, additives, ingredients and sodium. Also taste. Toenails would be better.

My housekeeper’s Guyanese. Muslim. Into halal meats. Her Indian sister’s Hindu. To them, a cow’s sacred. The Filipino brother-in-law’s Catholic. The nephew’s dating a Jewish girl. I am not inviting this group over.

Then there’s the lactose intolerant. Milk products are out. I know a lady who has violent reactions to shellfish. Another can’t do red, green or yellow pepper. One can’t do whey. Why? Who knows. Some can’t eat wheat or gluten.

We’ve got medical practitioners, dieticians, nutritionists, allergists, specialists, pharmacologists, cardiologists and assorted chefs. Herman Tarnower’s Scarsdale Diet. The water diet. Grapefruit Diet. Low-fat diet. High-fat diet. Raw food diet. Zone diet. Jenny Craig. Weight Watchers. Whatever Medifast is. The Pritikin thing.

Now, the Mediterranean diet. Jazzy, my Yorkie, 4 1/2 pounds, is allergic to beef, carrots and wheat. I’m going to shove olive oil and red wine into him. Whatever the results, it’ll be cheaper than my vet.