Here are some simple guidelines to prevent it.

Your diet is a bank account. Good food choices are good investments. — Bethenny Frankel

EDITORIAL DISCLAIMER: Any advice or recommendation given in my writing is what works for ME and may not be the best regimen for you based on your psychological or physiological makeup and stability. Please consult a doctor when making decisions about your health.
When I started working for my current company in sales more than 15 years ago, I was amazed that we actually got an expense account to take our clients to all types of meals and charge it back to the company.
For someone like me, who never had the chance to go to anything nicer than a Golden Corral growing up, eating out at a sit-down restaurant in which someone actually took your order and waited on you was a pretty big deal.
For that reason, when I first started to eat out with my clients, I would pretty much get whatever I wanted because this was new to me, and I was going to enjoy all the frills that eating out every day on the company dime had to offer.
It didn’t take me long to realize, however, that if I kept eating all the different dishes that looked and sounded amazing, I was going to quickly find myself focusing more on losing weight than gaining clients, as I was quickly adding the pounds based on this habit.
This is where I began developing my eating-out guidelines to ensure I didn’t gain the infamous “Newbie Twenty” that everyone said you would gain in the first year at my company.
However, as the pandemic developed and I began to reduce my calorie count tremendously as a result of learning what was healthier for me in the long term, it was time to refine my standards again to a method that allows me to stay within my 300–400 calorie count per meal.
Start with a salad
I’m sure you would’ve guessed this one, as this is what most people would associate with a healthy meal at a restaurant. This is definitely correct, and I personally suggest looking for a mix with mostly kale or spinach, if possible, as these are known as great superfoods for the body.
Any mix will work, however, so choose the one that you like the best. You also want to look for ones who have a variety of other vegetables and things like fruit or nuts on them to give you a bit of variety and color — something that is important when you eat the same meal type mostly.
Remove any extra cheese and bread-like substances
Cheese and carbs are definitely your enemies as it relates to eating out.
When you are making a dish at home, you can use 2% or fat-free cheese to keep your calories low, but when you eat out, the chances of this happening are slim to none.
Cheese is a huge calorie add to salads, as usually it is spread on indiscriminately because most customers love it. This is the same for bread or croutons or any type of tortilla strips.
Adding them to your salad can add 100s or maybe up to 1000s of extra calories to your salad, and this would completely defeat the purpose of getting a salad in the first place. This is part of why taco salads are considered pretty much the worse thing you can get at most restaurants. You could have gotten that burger you wanted instead, so your sacrifice and discipline to get salad would’ve been wasted.
Don’t let that happen. Stay away from all bread and cheese.
Add grilled chicken or salmon
Of course, you don’t want to get anything fried, as that would also defeat the purpose, so one needs to generally opt for grilled chicken or salmon to add to your meal.
Salmon is great to try to eat once or twice per week if possible, as it adds the healthy fats (omega 3 fatty acids) our heart and brain need to continually stay healthy and thrive.
Grilled chicken is generally a staple of most health meals, as it is often so lower in calories and such a great source of protein that choosing it is generally a no-brainer.
One could also get steak from time to time (I usually have a steak dinner once per quarter) if desired, but this would add a few extra calories to the meal and likely take you out of that 400 calorie range, so I would only do it sparingly, if at all.
Only use vinaigrette dressings…NEVER cream-based
The following strategy has worked well and one should be able to duplicate it at almost all types of restaurants.
These days, many restaurants will put the calories of whatever dressing they are serving on the menu. If not, you can often easily find out what the calorie count of most dressings is by Googling the name of the restaurant, the name of the dressing, and “nutritional stats.”
Also, if you are using MyFitnessPal, this can help tremendously.
While this doesn’t always work, it should yield results about 50% of the time. For the other 50%, I usually just focus on choosing any type of vinegarette dressing they have.
Most of the time, these are going to be the lowest calorie dressing, as they are vinegar-based which typically has no calories. Balsamic vinegarette and raspberry vinegarettes are two of my go-tos as you typically know that you are going to get the healthy version of it at almost any restaurant.
I have been in situations in which the vinegarette has had more of a confusing name, e.g., ranch lime vinegarette, and I had to ask to be clear. Sometimes, they fuse the vinegarette with another type of dressing and completely kill the lower-calorie part of it, so you will want to ask to make sure whenever you are forced to make a choice of something of which you are not familiar.
I always typically ask for mine on the side as well in the event it still isn’t what I expected, and I can easily switch it out instead of having to ask the kitchen to remake my entire salad, something that could put your returned dish in danger of not being the “best prepared” if the cooks are not in a particularly good mood.
Option if there are no salads
For me, in this day and age of health-conscious people all over the world, if a salad isn’t an option in a restaurant, I just don’t eat there.
There are just too many places that understand this is a major demographic to be successful, and, therefore, caters to them accordingly.
However, if you do find yourself in an establishment that doesn’t have this as an option, you can just use their calorie outline to see what is lower that will not ruin your diet.
If they also don’t have calories on their menu, you can then try old faithful Google or MyFitnessPal to see what dishes are possibly the best to stick with your diet regimen. By just typing in the name of the restaurant and “nutritional stats” again, you can often pull up the nutritional menu of most dishes at most major restaurants.
If this still fails and you cannot find anything online to give you some guidance and there are no other options available, I would just go with a combination of grilled chicken of some kind and mixed vegetables.
As shared earlier, grilled chicken is just one of the lowest-calorie items you can put on your plate, and you typically can’t go wrong with mixed vegetables. Just like balsamic and raspberry vinegarette are my go-to’s as it relates to dressing, this is always the fallback meal that will always keep me on point almost wherever I go.
And while I can’t promise that this will be the most appetizing meal you will ever have in the moment, at least you’ll be happy knowing that you stayed committed to your diet in the face of challenging circumstances, which, in turn, makes that cheat meal taste so much better when you enjoy it over the weekend.
