I’m Trying A 50-Day Vegan Diet Challenge And It’s Rough

One runner is in the middle of a vegan challenge but isn't feeling well after the changes—and it's starting to affect her training.

I am three weeks into a 50-day vegan challenge. There are a few things I’ve noticed changing in my body/life—some are great and some are not so great. Some were surprises and some I read about. But here’s the thing: I don’t feel so great (and I’ll give some more detail below). Each week has been progressively worse when it comes to how I am feeling. I am going to need to make some serious changes or abort mission if I want to keep marathon training.

Just for some background, the majority of my meals are made up of some combination of: Quinoa, lentils, beans (garbanzo, black or cannellini) spinach, kale, carrots, peppers, broccoli, nuts, tempeh, tofu, Vega protein shakes, almond milk, soy milk, bananas, apples and hummus. I am using a service called Lighter (which is pretty fabulous) and they make sure I have more than enough whole vegan foods.


  • I am exhausted. I’ve been sleeping 8-10 hours a night (as opposed to my usual 7-8), and I am still exhausted by the end of the day. The plus side to this? I am getting a solid night of sleep—no disruptions or middle-of-the-night tossing and turning. But the downside? I’ve slept through two morning runs for the first time in my life. Slept straight on through two blaring alarms. I’ve started taking a B12 supplement to see if this helps.
  • I am hungry very often and it comes on suddenly. I used to get little hunger aches, then bigger ones, then I’d get irritable, then nauseous. Now, I am furious and nauseous all of the sudden until I eat. Repeat every two to three hours.
  • My hair is falling out. Out of my head. Right onto everywhere around me.
  • My focus is terrible. It’s taking so much more energy for me to focus on my work. I am usually a very high-energy person and for the first time, it’s a challenge for me to get through my day achieving all that I want to.

There are some pros, but unfortunately, not one has to do with how I feel.


  • I am saying no to a lot more junk food and I am losing some weight.
  • I am diversifying the beans and kinds of vegetables I include in my diet.
  • I am learning to cook! My “Does cereal count?” days are over.
  • I am awesome at reading food labels.

I’ve learned a lot so far on this journey. A few things are for sure: I will include more vegan meals in my diet and I will cut out dairy. But there are a few foods I believe would make me feel better: fish and eggs. These are the foods I am contemplating reintroducing into my diet.