There are a ton, but here are some of the main ones.

1. Dining out and eating in social settings

As many vegetarians know, one of the biggest challenges of vegetarianism alone is going out to eat. The same is true, maybe doubly so, for vegetarian keto.

People are always going to ask you to go out to eat with them and be social, but the selection of restaurants that offer truly vegetarian keto items is shockingly small. When you go to parties or have potlucks at work, you may often find yourself unable to enjoy the foods provided.

This doesn't mean you should become a hermit.

A better alternative is to eat before going out, bring your own meals to work, or suggest local restaurants that you know have options for you. In order to avoid being super awkward, don’t stuff yourself before you go out, just eat enough to feel fulfilled, then you can order some side dishes/vegetables/salad or a single veggie burger without the bun. Most places are starting to adapt to the veg crowd, so you should be able to find at least something to nibble on, but always have a list of good places ready that you can defer to if asked. Indian restaurants are great for veg keto, same for Middle Eastern restaurants.

If you do find yourself in a restaurant, here are some options you can defer to:

Most large salads should be okay, and this will be the majority of your foods

Ask for a veggie burger (find a restaurant near you with the Impossible Burger, or get the Beyond Burger from T.G.I. Friday’s, Twin Peaks, or BurgerFi) with a lettuce bun (Jimmy John’s has the unwich that can be done up vegetarian)

Ask if you can replace fries or chips for some broccoli or a side salad

For breakfast, scrambles will be your best friend - try and go to restaurants that serve all day breakfast (Denny’s, Cracker Barrel, IHOP, etc.)

Indian cuisine has a lot of low carb options as well (anything with paneer: paneer tikka, butter paneer, cauliflower curry, lots of other options too)

Mexican food is doable as well: veggie fajitas without the tortilla (some places will let you sub lettuce as a wrap), taco salads, burrito bowls, huevos rancheros, cheese chili rellenos, rajas, queso fundido, etc., but skip the rice/beans/chips

Thai food: coconut curry, vegetable dishes with tofu subbed for meat, eggplant, tom kha tofu soup, etc., just make sure to ask for no fish sauce and to hold the rice (thai places also tend to up the sugar in their dishes too, unfortunately: go with garlic sauce over other sauces)

Itaian: vegetables in cream/Alfredo sauce, caprese salad, zucchini noodles (Noodles & Co. does this), eggplant parmesan, cheese platters, Alfredo (sub pasta for extra veggies)

Fast food: Chipotle/Qdoba (salad bowls with veggies/guacamole), Moe’s (salad bowls), Panera (Greek salad), Jimmy John’s (unwich vegetarian style)

This is going to be tough, but always ask your server for help. Usually they’ll be more than happy to help you find what you need (especially since they’re expecting a tip). Look out for side/garnishing sauces or glazes, many of which will contain a lot of sugar. Most restaurants have their nutritional information online somewhere, so take a look at their options online before you go or on your phone while you’re there.

Related: alcohol with vegetarian keto.

One solid piece of advice is to, no matter how tempting it is, try to avoid telling anyone that you've started vegetarian keto. I know many people use this as a tactic to publicly commit themselves to a diet, but a niche diet like this comes under a lot of ridicule. Having people intruding on and questioning your personal choices so much can be discouraging and frankly, annoying. Share at your own risk.

2. Getting enough nutrients and calories

Vegetarians are often harassed about protein and other nutrients that are primarily derived from meat. While vegetarians do often face a lack of nutrients, protein is not usually one of them. Dr. Heather Fields of the Mayo Clinic weighs in:

Vegans have not been shown to be deficient in protein intake or in any specific amino acids.

She also says that there are other nutrients that vegans tend to lack, which may or may not be true for vegetarians as well.

If you’re interested in finding out what nutrients you actually might be needing more of based on your age, body, activity levels, etc., check out this calculator from the US Department of Agriculture. However, vegetarians have been known to lack nutrients including but not limited to iron, vitamin B12, and vitamin D (read more about deficiencies below). While supplements for these deficiencies are fairly easy to get, you should check with a doctor to make sure you need them before purchasing.

With a diversification of foods from different sources, very rarely should you need to supplement your diet for vegetarian keto. If you know you need supplements, scroll down or click here to read more about which ones I recommend and why.

As far as calories are concerned, you will come to find that many of the high-carb foods you are cutting out were the same foods that contributed so many calories to your diet. A restriction in food groups naturally leads to a reduction in calories. Ketosis also suppresses appetite, however, so you really need to make sure you're bringing in enough calories to keep your body happy and healthy.

The best source of extra calories for the vegetarian ketogenic diet is through fats. Don't be afraid to add a little extra olive oil or coconut oil when you need more calories in a meal!

Another option to increase your calorie intake is to switch your regular coffee grounds with Bulletproof coffee. For those of you that aren't familiar with Bulletproof coffee, it is essentially these ingredients put into a blender:

2 cups of coffee

2 tbsp of unsalted butter

1-2 tbsp of MCT oil

Alternatively, you can use Instamix powdered creamer to just add to your cup of coffee in the morning. Bulletproof coffee should help your energy levels and help you maintain your coffee drinking habits through your vegetarian keto journey.

3. Avoiding unexpected carbs

Unfortunately, carbs are secretly in everything. Once you start consistently reading the nutritional labels of your foods, you'll realize that food manufacturers are constantly trying to put sugar in the weirdest foods. Chili, peanut butter, fake meat, etc. sometimes have significant grams of sugar in them that could add up over the course of a day.

The best option is to, of course, read your nutrition labels thoroughly and track your nutrients using one of the apps mentioned here. For vegetables or foods that you pick up at the farmer's market or other food that lacks nutritional information, this spreadsheet covers the carb count for a huge number of foods and drinks. This spreadsheet will save you so much time.

4. Not feeling the greatest, especially near the beginning - keto flu

If you've never tried a keto diet before, then your body has been energizing itself from glucose for essentially your entire life. Around day 3 or 4 of starting keto you may find yourself having intense cravings for sugar or starches - this is when you know that your body is nearing ketosis. There are other symptoms that may come up too.

These feelings and symptoms are referred to as keto flu.

Here are some of the reported symptoms of keto flu:

aches and pains

low energy levels

fogginess of thought/dizziness

trouble sleeping

heart palpitations

So, what exactly causes keto flu? How do you cure keto flu? Interestingly, all of these symptoms come from the same problem: a lack of electrolytes. Let me explain.

Transitioning to keto makes you have to urinate more often. Because of this, electrolytes are constantly leaving your body through urine. This deficiency is what makes you feel so crappy.

Click here to see the writeup on the cure(s) to keto flu.

The above are just some of the challenges you might face on a vegetarian keto diet. Each person's body responds differently, so your mileage may vary.