Grain-Free, Legume-Free, Sugar-Free Experiment

For the month of August, I’ve been doing a new dietary experiment. I’m eating grain-free, legume-free, and sugar-free. I’m doing this mainly out of curiosity to see what effect it has. I think I’m far enough along (about four weeks) that this would be a good time to share what I’ve learned.

The biggest adjustment was switching some common food sources, especially carbs. Instead of brown rice or rice noodles, I’ve been eating more potatoes, sweet potatoes, and starchy squash. Instead of beans or tofu, I’m eating more fruit, nuts, and veggies.

While I’ve removed refined sugar sources like coconut sugar and maple syrup, I’m still having some sweet fruit, including bananas, berries, and peaches. I’m allowing but limiting dried fruits, so I normally won’t eat more than 2-3 dates in a day.

This was a fairly modest adjustment. I still like all the foods I get to eat, so it doesn’t feel like a sacrifice. I just focus on a different subset of the wide range of foods I like. One favorite meal I’ve been eating more often is a big plate of roasted potatoes, red peppers, and sweet onions.

I’ve also been eating a lot of salads. One of my favorites includes romaine or mixed greens, shredded cabbage, cherry tomatoes, cucumber, avocado, 10g olive oil, 24g balsamic vinegar, and a sprinkling of seasoning (nori, kelp, sesame seeds). I often eat this with some olives on the side.

I haven’t noticed too much difference in terms of mental and physical differences, but there is some.

The main difference is that I feel less hungry for much of the day, especially between meals. I’m eating slightly less because of that, but most days I’m still coming in between 2000 and 2200 calories. At first I felt some cravings for certain foods, like a rice bowl, but those went away after the first week.

Exercise-wise I haven’t noticed any meaningful difference. I like to begin most days with a 5-mile run, and my runs have felt about the same this month. If there’s a difference one way or another from this dietary change, it’s too minor to detect. Or it’s possible it make take longer for there to be enough of a difference to notice.

The main effect I do notice on my runs is that if I don’t eat enough on the previous day, I feel more tired and sluggish during my run the next morning. So if I only eat 1800 or 1850 calories instead of 2000+, I feel less energetic the next day when I go running. Running feels a bit harder, especially when going uphill. That’s true even if I have a big dinner the previous day; the day’s total calories matters more than the size of the previous meal. So even if I don’t feel hungry enough to need those extra calories, I find it best to eat at least 2000 calories per day. I also experienced this same effect before doing this dietary experiment, but with this different way of eating, it’s easier for me to feel satisfied on fewer calories, so I’ve “run” into this issue more often this month.

I also notice a difference in mental performance if I eat too little. Some days I’ve felt a little mentally sluggish and then observed that I haven’t been eating enough relative to the time of day. So I’ll eat some more food, maybe 200 calories if I just want a snack, and this helps my mind feel sharper. It’s been interesting to observe this connection between food intake and mental performance. Multiple times I’ve made the mistake of eating too little, but I didn’t notice that I wasn’t eating enough till I tried to do some mental work and felt unmotivated to do it. Fixing the problem is as easy as eating some fruit or nuts.

Emotionally I haven’t noticed any discernible difference. I normally feel emotionally stable and positive, and I don’t sense any changes in that area this month. When I eat 100% raw, I notice a significant improvement in mood within the first few days, but that hasn’t happened with this diet.

After about four weeks of this dietary experiment, I feel the benefits are relatively modest, given the trade-off of narrowing my food choices. I do like that this different way of eating has encouraged me to explore different meal options, like the peach bowl I shared yesterday (which I had again this morning). I’ll at least finish off the full month, but I’m not seeing enough benefits to warrant a long-term change here.

I am curious, however, if the reduction in hunger between meals is due to removing grains, legumes, sugar, or some combo of those. So I may try reintroducing some foods slowly next month to see if I can gain more awareness there. You may have your guesses, as do I, but I gain the best insights from seeing how my body and mind actually respond, which often doesn’t match people’s predictions.

In terms of results, tweaking which plant foods I eat doesn’t seem like nearly as big of a deal as getting all animal products out of my diet. That was the most important step, especially given the long-term mental and emotional gains, many of which were very noticeable in the first week or two. The biggest deal beyond that was to eat 100% raw for a while.

I’ve continued to lose weight this month (I lost another 5.8 pounds during the 4 weeks of this experiment), so this diet hasn’t interfered with that. I have been losing weight a bit faster this month than before, but it’s hard to say if that’s significant. I think it’s too little time to know for sure.

I’m still keeping a food log of everything I eat, and that simple habit alone has made it really easy to lose weight. I’ve been doing daily food logging for 15 weeks now, and I’ve lost 18.8 pounds in that time, which is an average of 1.25 pounds per week. This has felt practically effortless. Just taking a few minutes per day to write down what I eat has raised my awareness of exactly how much I’m eating each day.

Food logging has been such a nice tool for raising awareness that it’s creating results without my having do deliberately do anything more. It’s very different doing it for 15 weeks in a row versus doing it for only a few days or a week. I intend to maintain this tracking habit at least through the rest of the year because I’m still learning from it, and it really is super easy to keep doing it after 105 days of consistency. Another 100+ days seems like a breeze.

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