Pressing pause on your weight-loss goals during happy hour can turn your 100-calorie drink into an 800-calorie one.

Whats worse, those calories are basically empty, unlike the food you consume.

Calories from food provide energy for you to go about your day and [give you] the nutrients your body needs to thrive, says Amy Gorin, MS, RDN, owner of Amy Gorin Nutrition in the New York City area. If you eat an apple, for example, youre not only getting the calories from that appleyoure getting cholesterol-helping fiber along with lots of vitamins and minerals.

Not so with your favorite cocktail, explains Gorin, where the calories dont come with nutrients that your body needs. Does this mean you have to forget your Friday night meetup with the girls? Nahits still totally possible to drink alcohol while trying to lose weight.

I typically tell clients to choose their indulgence...if youre trying to lose weight, you may not want to go for the dessert and the alcohol every day, but you definitely can make room in your diet for one or the other, says Gorin, who adds that a 100-calorie drink on its own isnt going to sabotage your goals.

What do I need to know about better boozing habits before I hit the bar?

First, keep it simple: If you can take your gin neat with a squeeze of fresh lime, your waistline will be better off than if you went for the standard, sugar-loaded G&T (yeah, there's sugar in that tonic water). Second, stay away from mixed drinks that include more than one alcohol.

Once you start using more than one type of booze, your calories really start to get up there, says Keri Gans, R.D., author of The Small Change Diet . A Long Island Iced Tea? Forget it.

Let's get to the good stuff: What alcohol is best to drink on a diet?

Most alcohol does about the same damage, calorie-wisethere's really not a huge difference between vodka and gin (or whiskey, rum, bourbon, scotch, and tequila).

The number one thing to keep in mind is the mixer, says Gans. Almost all shots of alcohol are about the same nutritionallyits what we have with it that makes a difference in the drink, she says.

Gorin agrees, adding that your best bet for ordering the lowest calorie alcohol is starting with whiskey or scotch and adding water (to help open up the flavors!) or a no-calorie mixer like club soda.

Whats the highest calorie drink?

Again, it mostly depends what youre adding to it...but Gorin says frozen drinks typically have added sugar, which means added calories (a frozen margarita can come in at a whopping 800 calories).

Gans agrees: Do not have a frozen drink if youre watching your weight.

Can I make easy swaps to lower the calories?

Yup. Ask for a margarita with less agave, a mojito with less sugar, says Gorin. Ask if the bar is serving 100% juice or a juice cocktail, which is a keyword for added sugar and calories.

Need a quick tip sheet for ordering a drink without maxing your weight-loss goals? Here are the best and worst options for the most popular spirits:

Vodka

One shot contains: 97 calories, (0 sugar, 0 carbs)

Best drink: Vodka soda

Zero calorie seltzer might be basic but it also helps you stay within your calorie budget. Add a squeeze of fresh fruit for a little more pizazz.

Worst drink: Sex on the beach

In general, stay away from juice mixers, says Gans. They can up your sugar count fast. (That means no vodka cranberries or vodka lemonades.) The peach schnapps in a sex on the beach will really put your vodka over the edge with roughly 336 calories and 32 grams of carbs and sugar. Ouch.

Rum

One shot contains: 97 calories (0 carbs, 0 sugar)

Best drink : Rum and diet coke

Rather than your go-to rum and Coke, make it a diet to cut calories.

Worst drink : Pina colada

The sugar-laced coconut-pineapple concoction turns a regular rum into a diet saboteur. The average cocktail packs 245 calories, 32 grams of carbs, and 31 grams of sugar. No bueno.

Also try : Rum and unsweetened black tea

Gorin recommends trying this combo if youre looking for something delicious to warm you up. One cup of unsweetened black tea will only add about two calories to your bev, so the whole thing still comes in under 100 calories.

Whiskey/bourbon/scotch

One shot contains: 105 calories (.03 grams of carbs per ounce, .03 grams of sugar per ounce)

Best drink: Manhattan

Don Draper was on to something. If you dont want to drink your whiskey straight, order a classic Manhattan (whiskey, sweet vermouth, bitters), which keeps calories, carbs, and sugars low.

Worst drink: Whiskey Sour

Get fancy with a with a whiskey sour and youll run into trouble thanks to the simple syrup. One cocktail rings in at 240 calories, 24 grams of carbs, and 23 grams of sugar.

Gin

One shot contains: 110 calories (0 carbs, 0 sugar)

Best drink: Gin martini

Channeling your inner Bond girl will serve you well if youre watching the scale. A gin martini with two olives is under 200 calories and contains no sugar or carbs. Hollah!

Worst drink: Gin and tonic

A classic gin and tonic is also pretty low calorie, but tonic water is laced with a surprising amount of sugar. One serving will add 21 grams to your daily diet, which just about the 25 gram per day limit suggested by the World Health Organization . If you cant break with tradition, go for diet tonic.

Tequila

One shot contains: 105 calories (0 carbs, 0 sugar)

Best drink: Paloma

The tangy pink drink, made with grapefruit and lime juice, is like a margarita without the extra calories. However, it is juice-based, so dont go overboard with your grapefruit juice mixer. Opt for the fresh-squeezed stuff if you can.

Worst drink: Margarita

If youre trying to tone up, you might want to toss marg night. Margaritas, whether frozen or on the rocks are loaded with enough sodium and sugar to tip the scales against you even if you skipped the guac. A typical frozen marg can weigh in at over 600 calories and over 80 grams of sugar. Yikes.

Champagne

One 4-ounce glass contains 90 calories (3 carbs, 1 sugar)

Best drink: Champagne and seltzer with fruit

A 4-ounce glass of bubbly isnt muchbut you can fill up the rest of your flute with seltzer and fresh fruit or mint leaves for a drink thats yummy and low-cal.

Worst drink: Mimosa

Even the worst champagne drink isnt all that bad, but when you add sugary orange juice to your brunch booze of choice, it could clock in closer to 150 calories instead of a cool 90. (To make an 8-ounce mimosa, you would need about four ounces of OJ , totaling an extra 50 calories and nearly 10 grams of sugar).

Beer

One 12-ounce bottle contains 153 calories (13 carbs, 0 sugar)

Best drink: Light beer, which Gorin says is a good way to save calories. Try Miller 64, which is one of the lowest calorie alcohol options out there.

Worst Drink: Guinness (the Extra Stout brew has 176 calories!). Those fancy european beers may pack in more calories than you think, because typically the higher the alcohol percentage, the higher the calorie count, Gorin explains.

Wine

One 5-ounce glass of wine contains 123 calories (4 carbs, 1 sugar)

Best Drink: Red wine. Nutritionally, theres not much difference between red wine and white wine, but there are other benefits in choosing a pinot noir over a chardonnay. Gorin says red wine might have some nutritional benefitslike a possible boost to cardiovascular health so even though you should still consume in moderation, its an overall smart choice.

Worst Drink: Sangria. If youre making this at home by tossing some fresh fruit into your favorite vino, youre good to gobut if youre ordering a sangria from the bar, you could be drinking a whole bunch of added calories from any fruit juices or other alcohols (like brandy or flavored liqueur) they put in. Ask before you imbibe.

Baileys

One shot contains 147 calories (11 carbs, 9 sugar)

Best drink: Baileys and coffee. Gorin says adding a 1.5-ounce shot of Baileys to a cup of decaf only nets you 149 calories (coffee is, thankfully, almost no-cal).

Worst drink: Duh, a mudslide. If youre craving a mudslide, Gorin recommends curbing that craving with the aforementioned spiked coffee since a traditional mudslide has 740 calories (wow!).