What I wanted to know when I started eating a low FODMAP diet, resources for a low FODMAP diet, and what to explain to family and friends about the FODMAP diet

As part of my pandemic “fun” (but fortunately not from COVID-19 infection, which I’ve avoided), I developed some gastrointestinal dysbiosis. Gastrointestinal dysbiosis generally means microbiome dysfunction of some kind, hypothetically caused by a loss of ‘good’ bacteria and getting out of balance with ‘bad’ bacteria. I don’t have a diagnosable disease such as IBS (that and many other things were ruled out through a variety of medical testing), but I definitely have some dysfunction going on causing varying levels of GI symptoms now for almost a year and a half. At their worst, I was waking up overnight suddenly with sharp abdominal pain out of the blue – scary! At their least annoying, it was excess gas and general abdominal discomfort after eating. It ebbed and flowed and did not seem to be traceable to any particular cause. After several months, I consulted a gastroenterologist and did an assortment of tests over the course of ~10 months, slowed down by the pandemic and my reluctance to do in-person clinical tests until I was fully vaccinated against COVID-19 (we checked for c-diff and inflammation among other blood tests, did a CT scan, and eventually did a colonoscopy and endoscopy). The test results all came back normal. Eventually, we decided on a treatment plan that involved an antibiotic to kill excess bacteria in my small intestines. That worked – for about two weeks – and then my symptoms returned. I needed another solution, and before I went back to my gastroenterologist to talk about more extreme options, I decided first to self-test a low FODMAP diet.

(As a note to those who don’t know – I have had type 1 diabetes for almost 19 years, and celiac disease for about 13 years. As a result, I’ve been 100% fastidiously gluten free for 13 years and already eating a gluten free diet. P.S. I’m not a doctor and nothing in this post or this blog is medical advice.)

Header image: What I wanted to know about starting a low FODMAP diet and how I explain low FODMAP to family and friends

What a low FODMAP diet means in simplified terms

FODMAP is an acronym for different groups of short-chain carbohydrates, or sugars, that can cause symptoms for some people when they eat them, because the small intestine absorbs them poorly. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols.

The FODMAP diet is often discussed in the context of IBS (one particular condition), but it can be used by people with a variety of gut dysbiosis issues, many of whom (like me) don’t necessarily have a diagnosable condition or disease.

One reason I decided to try a low FODMAP diet is because I had identified onion and garlic as potential food-related triggers or variables that correlated with some of the worst of my symptoms. I began attempting to eliminate onion and garlic (and then onion powder and garlic powder) from my diet from January 2021-May 2021. It helped, but I was still having varying levels of symptoms.

Generally, people who describe being on a low FODMAP diet are referring to the first step of a three-step or three-phase diet. The first step is eliminating the major sources of FODMAPs. Then, a careful re-introduction process takes place to “test” and see which of the groups of FODMAPs you react to, and in what amounts. With that knowledge, the third phase is then eating what you’re willing to eat based on your knowledge of what FODMAPs bother you and what you’re willing to tolerate symptom-wise.

What most people don’t realize at first is that the amount of FODMAP and type of FODMAP matter, in each of the phases.

For example, there are a lot of blog posts and lists that will describe things that are “low FODMAP”. And they are partially right, but they leave out specifications that if you eat too many of them, the FODMAP amount may be considered “high” (meaning likely to trigger symptoms). Additionally, you can eat multiple things with the same type of FODMAP and cause FODMAP stacking, meaning you cumulatively have too much of the group of FODMAP and can cause symptoms, even if you ate the “right” low FODMAP portion of each individual food. Sometimes eating the same group within a short period of time can cause stacking, and so spreading them out 3-4 hours apart (or longer) could help reduce the effect.

(P.S. If you are looking for a simplified explanation to share with family and friends, skip to the bottom of the post!)

Resources for getting started with low FODMAP diet and some pros and cons to each

There are many blogs out there that will describe FODMAPs and the process of FODMAP elimination pretty well. Many have short lists of examples of foods that are “high FODMAP” and to avoid. The challenge, as I mentioned, is that the amount of food matters and knowing the type of FODMAP it contains really helps. There are many “high FODMAP” foods that you can eat in small quantities, and it’s also possible that you can eat large quantities of “low FODMAP” foods and accidentally stack FODMAPS from the same group and cause symptoms. With this diet and process, knowledge is power (even though it is very annoying to have to read ingredient labels and super sleuth everything you eat…).

There are several lists or spreadsheets of low FODMAP foods. Here is one that I found that is freely available. It lists the ingredient, it’s “max use”, and has information about the FODMAP group. This is information pulled from the Monash app and may be out of date – same with many blog posts or online lists you might find, such as this one!

How I used many of these free lists and blog posts was to get a sense of “green” or “low FODMAP” foods. There are a few types of foods that are really “free” meaning you can eat as much as you want because they don’t contain any level of FODMAP, so they shouldn’t affect you regardless of the quantity you eat. I first made a list of these “free” foods (I’m probably pulling this “free” terminology from early-2000-era diabetes food terminology) that I actually like and want to eat. For example, for me, this was eggs, grits, carrots, baby corn, peanuts, most cheese, and popcorn. This is what I ate for the first handful of days while I was doing my research on what else would constitute a low FODMAP diet. It sounded and felt restrictive, but thankfully as I learned more I realized that I could eat a lot more things and a better diversity of things.

The next app/tool that helped was the Monash app. One caveat – it costs money. I waited a few weeks before I finally caved and paid $8 USD for it. The reason I finally decided to get it (vs using tools like that spreadsheet above and other places that have information from Monash available) is I wanted the quick visual glance the app has about whether the food is completely low FODMAP and ‘free’ to eat (e.g. carrots, eggs) or low FODMAP in certain portion sizes, or pretty much high FODMAP no matter what. Monash is a university in Australia that does most of the research and testing on FODMAPs in foods, so I decided paying for the app was a way to invest in the research that I’m clearly benefiting from.

Example from Monash's app showing different color orders
Example from Monash’s app showing different color orders

I do have some frustrations with the Monash app, though. It only includes foods that they’ve happened to measure…which is a good amount, but not as many as I’d like. It also confusingly sometimes lists the different serving sizes in opposite order. For example, there might be a “green” overall rating, with a certain portion size indicated in green but also showing the yellow/amber “moderate” amount portion size alongside the red “high” portion size, so you can see the difference. However, sometimes they list the portion size in opposite directions. This search for bananas is a good example – the color indicators on “Banana, sugar (ripe) goes red-amber-green; the color indicators on “Banana, common (unripe)” goes green-amber, and the color indicators on “Banana, common (ripe)” goes red-amber-green again.

Their rationale for this is that standard serving size and traffic light rating will always be the first traffic light so foods may start green and go red as serving sizes increase or start red and become green with smaller servings. However, it means as a user that you have to pay close attention to the order and serving sizes and it’s not the same across the app.

You also have to pay attention to the tiny, grey text at the bottom below the individual ratings. The text isn’t the same from item to item. For example, peanuts are marked as green, no other color rating. When you click to see the details, it shows a portion size of 32 nuts (0.99 ounce), and the text indicates the portion only contains trace amounts of FODMAPs and “eat freely according to appetite”. Same for carrots, so these are what would constitute a “free” food where you don’t have to worry about FODMAP stacking.

However, when you look at pecans, it also has a green overall rating. But the serving size is 10 pecan halves (0.71 ounce) and the grey text indicates that “Large servings (40 pecan halves or 100g/3.5oz) contains moderate amounts of the Oligos-fructans and intake should be limited.”

Example of Monash's app showing peanuts as the result
Example of Monash’s app showing peanuts as the result
Example of Monash's app showing pecans as the result
Example of Monash’s app showing pecans as the result
Example of Monash's app showing the search result with peanuts and pecans
Example of Monash’s app showing the search result with peanuts and pecans

 

This means you can’t just eyeball the app and take the green overall traffic light rating, even if it just has a green overall rating and doesn’t have the additional lights (like under the bananas) indicating warnings about different portion sizes. The warnings about portion sizes may be hidden in the grey text that your brain doesn’t want to read because it assumes the text is always the same.

(The other thing I don’t love about the Monash app is that it’s language is very IBS focused. But there’s a lot of people using low FODMAP for non-IBS reasons, so you can mostly ignore that. It has other tools like a diary for symptoms and food intake and a re-introduction tracker for when you do re-challenges of FODMAPs.)

Another app resource is an app called “Spoonful”. It’s free: although you can pay something like $2.99 for a premium version, the free capabilities suit my purpose. You can scan a barcode or type and search for store-bought products, which is a great use case for me since I don’t cook a lot from scratch. It has different color coding (and you can limit your search to a color type) for whether a given food has low, moderate or high FODMAPs in one serving. It’s supposed to be dietitian-reviewed and approved. It’s good for gut-checking your interpretation of an ingredient label, but there’s a caveat that I’ve found several inconsistencies within the app (and already flagged and reported them). For example, I spotted a chip that was sour cream and onion and supposedly low (green rating) FODMAP *and* cited as officially certified as low FODMAP. Except…it has onion powder as a major ingredient and I am not sure it could be considered low FODMAP. (What I think happened is that Australia’s version of the company has a sour cream and chive chip that looks pretty similar and is certified low FODMAP, and they accidentally swapped them within the app.) I reported that one, and they were quick to fix it within days, so it  is now correctly marked as high FODMAP. In another search I did, milk and milk related products are flagged in one flavor of a food (e.g. an ice cream bar), but a slightly different flavor that’s still the same ice cream doesn’t have the milk ingredients flagged and has a completely different color rating as a result with those ingredients not flagged (in the same quantities). A third type of error I have found is that you can scan a barcode of a product, and the labeled ingredients listed in the app do not match the ingredients currently on the package – it’s pulling from a stored list of ingredients that could be outdated. So as a user, you have to eyeball and make sure the app listed ingredients matches the ingredients on the product in your hand, then compare any potential FODMAP-containing ingredients that are either flagged in the app or might be in your hand but not listed on the app, if those ingredient labels differ.

Hypothetically these are medium or small errors, but given the number of errors like that where they inconsistently flag ingredients across the same type of food item that result in variable color ratings, I would not rely just on their color rating and instead double check the ingredients yourself (including comparing them to the version you are holding in your hand). If you’re as sensitive to FODMAPs as I am, it’s worth double checking and thinking it through each time.

Additionally, the Spoonful app (as of August 2021) only supports one diet filter search at a time. Thankfully, I’ve had celiac forever and am comfortable knowing how to also determine if something is gluten free or not. So it’s not a big deal for me to “just” use the low FODMAP search to see what’s FODMAP-y or not, with the above caveats. But low FODMAP does not mean gluten free, even though some wheat-related items are high FODMAP, so do not use anything that’s low FODMAP as an indicator that it’s celiac-safe!

As another way of checking things out, it’s always helpful to google “Ingredient name FODMAP” or “Food name FODMAP” – often there are blog posts discussing the food type, or Reddit or similar forum posts discussing individuals’ experiences with that ingredient or food type.

However, one more important thing to keep in mind: it may be “low FODMAP” or “no FODMAP”, and it can still cause symptoms. Everyone is different, and that’s the point of needing to re-challenge each group to determine what groups bother you, and in what quantities. Additionally, some no-FODMAP foods or ingredients could be bothersome, and it has nothing to do with FODMAPs. For example, I noticed Crystal Light was bothering me last year and stopped drinking it. After I did the first phase of low FODMAP (the elimination phase) for a few weeks, I decided to test Crystal Light since it’s theoretically not containing FODMAP ingredients. However, it definitely caused symptoms that weren’t attributable to anything else, so it’s on my “don’t drink” list, just like onion soup would be, even though Crystal Light isn’t considered to have FODMAPs.

So how exactly do you do the different FODMAP diet phases?

Most everything I read online said the first phase, the elimination phase where you eat 100% low FODMAP, should be around 2-6 weeks. Another piece of data was that many dietitians recommend having 5-7 symptom-free days before starting food re-challenges (e.g. the second or next phase).

If you’re like me, you might get accidentally FODMAP’ed, as I call it, or experience FODMAP stacking by accident within your first few weeks as you work out the correct portion sizes of things and when to eat them. My rule of thumb was aiming for 2 weeks overall on the elimination/first phase, but also going for several days without symptoms so I had a “clean slate”, so to speak, before starting the challenges. I am lucky, relatively speaking, that I don’t have the major symptoms that most people with IBS who do FODMAP seem to experience – I don’t have diarrhea or constipation or that spectrum to deal with. My symptoms are usually noticeable immediately or within 12 hours, but they also resolve pretty quickly, so I can see the correlation between what I eat and the results fairly easily. As a result, I went a little more than 2 weeks attempting to do full low FODMAP elimination, had an extra few days added on due to some accidental FODMAP stacking, before I began my first “challenge” food.

The challenge foods should be ones that only contain one of the FODMAP groups. If you pick something that has multiple FODMAP groups, it’ll be hard to tell which FODMAP you’re reacting to or if it’s the stacking effect. I started with lactose (because I’m pretty confident already that I’m not lactose intolerant and it’s not an issue group for me) because it’s an easy one to start and cross off my list. The others I’ve personally decided to use as my test foods are cashews (Fructan+GOS); Apple (Fructose+Sorbitol); Raisins (Fructan: veggie & fruits); Almonds (GOS); Honey (Fructose); Sweet Potato (Mannitol); and Peach (Sorbitol).

Because I have celiac disease, I am of course skipping wheat bread and wheat pasta (Fructan: grain foods). I’m also skipping the separate fructan test for onions and garlic because I know I react to those and have already reverse-tested eliminating those in the past year. I might eventually test onion powder and garlic powder, but I’m de-prioritizing those to be after I test most of the others.

(The Monash app in the reintroduction section has several foods recommended for each group and the amounts for each, so that’s a good resource for selecting some of the challenge foods).

Two schools of thought for re-challenging: you can do day 1, 2, and 3 in a row with the increasing amount prescribed, or you can do every other day with a “washout” (e.g. fully low FODMAP) day in between. If you have moderate to major symptoms, you stop and have 3 washout days before you proceed with the next test. It’s up to you to decide what symptoms are tolerable and whether you proceed or cross that group off your list (for now). You can always come back and re-challenge or re-test groups or food at any time.

Finally, the third phase is what you get to when you’ve done all your testing and have an idea of what FODMAP groups are irritants or triggers, which foods as a result you want to avoid or continue to experiment with. Ideally, you arrive at a more diverse diet than the full elimination stage of low FODMAP. (Again, I’m not a doctor or dietitian, and I’m DIY-ing my low FODMAP experience, and these are all the conclusions I’ve arrived at after copious reading online and in the medical literature.)

What do you tell family and friends about the low FODMAP diet?

It depends, especially on what your lifestyle is and what stage of the diet that you are at (and also if you’re in a global pandemic which limits your eating-out options).

Because this experience has been during a global pandemic, I am no longer eating out at restaurants (to avoid being unmasked around strangers) which made things easier in the sense that I didn’t have to try to figure out low FODMAP restaurant options. But it was harder because I couldn’t even get gluten free takeout or delivery food anymore, and now have to make all my food myself. For the few social food situations I had with my in-laws (we are all fully vaccinated and use antigen testing to make sure we aren’t infectious on the days we visit in person), I have mostly decided to take my own food. I’ve stashed a few things in the freezer and pantry at their house to be able to make a meal and just let everyone else do takeout without me, so that we can all still sit down together for a meal. I have described what I’m doing and what it entails (such as avoiding onion and garlic and only eating particular things in particular amounts), but it’s hard to describe to most people at a high level because of the complexity of the types of foods (it seems random unless you think about the biochemistry) and the quantities. It makes me nostalgic for explaining only celiac to people, because “gluten free” is a much smaller category of ingredients to watch for and avoid, compared to FODMAPs and FODMAP quantity specifics. That being said, already being gluten free means I’m experienced at reading ingredient labels and have a head start on excluding some of the major FODMAP groups (fructan grain foods are usually gluten) and don’t have to (well, don’t get to) re-test those.

A friend recently said (because she’s amazing) that she wanted to read up on what a low FODMAP diet means, and I couldn’t find a good high level simple article to send to her, so I had to type up an explanation. So what I have summarized to her and family and other friends is this:

  • I have GI dysbiosis where I react to a lot of what I’m eating. I’m experimenting with a low FODMAP diet, which starts with a partial elimination diet to restrict the types of FODMAPs that I eat. FODMAPs are certain types of carbs that don’t digest well. During this stage, I’m avoiding things like onion, garlic, certain sweeteners, many fruits, and more. Even small amounts of these ingredients can make me feel bad, just like gluten, although they cause shorter term symptoms. What I can eat freely are plain meat and protein including eggs; vegetables like cucumbers, carrots, potatoes, and baby corn; and cheese, among other things. I need to check the ingredients on everything I eat, even things that we know are already gluten free.
  • Eventually, I will begin to “test” my response to the FODMAP foods. I’ll still be carefully managing what I eat while I do these tests so that I have a “clean slate” to see how my body responds to the type and quantity of each food. My hope is to be able to add some of the food groups back into my diet, but it may be only restricted amounts. It will be several months before I progress through all the tests.
  • I can use your support – I’m looking for low FODMAP alternatives to foods like X, Y, and Z, so if you’d like to help, in addition to listening to me vent, you could help me research some store-bought or homemade alternatives to these.

(One reason I add the “I can use your support” aspect for some people, which is obviously optional – I learned from being gluten free with celiac that having friends and family aware of what it takes to eat and find safe gluten-free options really cut down on the emotional labor required to find and suggest food every time. People try to be nice and let me offer gluten free options for eating out, but that means I have to do a lot of research every time. Having family members put the “Find Me Gluten Free” app on their phone and teaching them how to do basic searches so they could offer up suggestions, too, made a big difference. I won’t ask everyone for help re: FODMAP but for certain family members, they really can make a difference in doing some of the searching for low FODMAP alternatives to certain things that I haven’t been able to find yet! For me, this is things like finding a low FODMAP steak sauce that I could buy. I still haven’t found one. Thankfully, there’s also brands like Fody where I buy a lot of sauces (BBQ sauce, spaghetti sauce, ketchup) and salad dressings – plus now they have tasty BBQ chips that are also gluten free, and meal delivery services like Epicured that I’ve tried. Note – I am not sponsored or paid by either of those brands, I shell out my own money for them!)

Mad-lib style fill in the blank template to customize telling family and friends about your FODMAP experience. It's the same text in the above personal description without the personal examples of food I like to ea.
Example fill in the blank script to customize to help you explain your FODMAP experience to family and firends

At the end of the day, the one thing you need to know about FODMAP is that everyone is different. Literally, you are a scientific experiment of one. What works for someone else doesn’t necessarily work for you. You know you, and you get to decide what level of symptoms you are willing to tolerate – or not – in response to different quantities of food. Whether it’s IBS, small intestinal bacterial overgrowth (SIBO), some other condition, or general gastrointestinal dysbiosis, a low FODMAP diet may be one option that you can try and see if it helps you feel better. In diabetes, we often say “YDMV”, meaning ‘your diabetes may vary’. In the landscape of GI-related stuff, I think it’s “YFWV”, meaning “your FODMAP experience will vary.”

Everything I did wrong (but did anyway) training for a marathon after a broken ankle and marathon running with type 1 diabetes

This is another one of those posts for a niche audience. If you found this post, you’re likely looking for information about:

  • Running after a broken ankle (or are coming from my “tips for returning to weight bearing” and looking for an update from me, two years after my trimalleolar ankle fracture)
  • Running with the “Galloway method”, also known as run-walk or run/walk methods for marathon or similar long distances – but with information about run-walking for slow runners.
  • Running a marathon with type 1 diabetes, or running an ultra with type 1 diabetes
  • Running a marathon and training for a marathon and going without fuel or less fuel

There’s a bit of all of this in the post! (But TLDR – I ran my marathon (finally), successfully, despite having a previously broken ankle. And despite running it with type 1 diabetes, I had no issues managing my blood sugars during even the longest training runs, even with significantly less fuel than is typically used by marathon runners.)

running a marathon after a broken ankle and with type 1 diabetes

First up, some context that explains why I chose run-walking as my method of running a marathon (as that also influences fueling choices) and what it is like to be a slow marathon runner (6 hour marathon ish). I broke my ankle in January 2019 and began running very tiny amounts (literally down the block to start) in summer 2019. I progressed, doing a short run interval followed by a walk interval, increasing the total numbers of intervals, and then slowly progressing to extend the length (distance and/or time) of the running intervals. In early fall 2019, I was attempting a couch-to-5k type program where I would extend my running intervals even longer, but I still had subsequent injuries (a very stubborn big toe joint, then intermetatarsal bursitis in TWO spots (argh)) that made this not work well. Eventually, I went back to running 30 seconds and walking 30 seconds, then keeping those “short” intervals and extending my run. I focused on time at first: going from 5 to 10 to 15 to 20 etc minutes, rather than focusing on distance. Once I built up to about 30 minutes of run-walking (30:30, meaning running 30 seconds and walking 30 seconds), I switched to adding a quarter or half mile each time depending on how I was feeling. But doing 30:30 seemed to work really well for me in terms of the physical impact to my feet, even with long miles, and also mentally, so I stuck with it. (You can go read about the Galloway run-walk-run method for more about run-walking; most people build up to running more, say 5 minutes or 8 minutes followed by a minute of walking, or maybe run 1 mile and then walk for a minute, or walk through the aid stations, but I found that 30:30 is what I liked and stuck with it or 60:30 as my longest intervals.)

This worked so well for me that I did not think about my right ankle a single time during or after my marathon! It took days to even remember that I had previously broken my ankle and it could’ve been problematic or weaker than my other ankle during my marathon. It took a long time to get to this point – I never thought I’d be forgetting even for a few days about my broken ankle! But two years later, I did.)

When COVID-19 struck, and as someone who paid attention early (beginning late January 2020), I knew my marathon would not be taking place in July 2020 and would be postponed until 2021. So I focused on keeping my feet healthy and building up a running “base” of trying to stay healthy feet-wise running twice a week into fall 2020, which worked fairly well. At the start of 2021, I bumped up to three runs a week consistently, and eventually began making one run every other a week longer. My schedule looked something like this:

Monday – 3 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – 4 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – 5 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – 6 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – (back to) 3 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – 8 miles  Wednesday – 3 miles   Friday – 3 miles

Monday – (back to) 3  miles  Wednesday – 5 miles   Friday – 4 miles

Monday – 10 miles  Wednesday – 3 miles   Friday – 3 miles

Note that these runs I refer to were all technically run-walks, where I ran 30 seconds and walked 30 seconds (aka 30:30) until I covered the miles. I was running slow and easy, focusing on keeping my heart rate below its maximum and not worrying about speed, so between that and run-walking I was often doing 15m30s miles. Yes, I’m slow. This all enabled me to build up to safely be able to run 3 runs weekly at first, and then eventually progressed to adding a fourth run. When I added a fourth run, I was very conservative and started with only 1 mile for two weeks in a row, then 2 miles, then up to 3 miles. Eventually, later in my training, I had some of my other runs in the week be a bit longer (4-5 miles) in addition to my “long” run.

But, because I’m so slow, this means it takes a lot of time to run my long runs. If you estimate a 15-minute mile for easy math, that means an 8 mile “long” run would take at least 2 hours. With marathon training (and my goal to train up to multiple 22-24 mile runs before the marathon), that took A LOT of time. And, because of my broken ankle and intermetatarsal experiences from 2019, I was very cautious and conservative about taking care of my feet during training. So instead of following the usual progression of long runs increasing 2-3 weeks in a row, followed by a “cutback” long week, after I hit two hours of long running (essentially 8 miles, for me), I started doing long runs every other week. The other week was a “cutback” long run, which was usually 8 miles, 10 miles (for several weeks), up to eventually 12-14. In terms of “time on feet”, this meant 2-3 hours “cutback” long runs, which according to many people is the max you should be running for marathon training. That doesn’t quite work for slow runners such as myself where you might be doing a 6-hour marathon or 7-hour marathon or thereabouts. (The standard advice also maybe doesn’t apply when you are doing run-walking for your marathon training.)

I had ~6 months to build up to my marathon (from January to the end of July), so I had time to do this, which gave me a buffer in my overall training schedule in case of scheduling conflicts (which happened twice) and in case of injury (which thankfully didn’t happen). I ended up scheduling training long runs all the way to full marathon distance (26ish miles), because I wanted to practice my fueling (especially important for type 1 diabetes marathon runners, which I’ll talk about next) as well as get my feet used to that many hours of run-walking. I did my long runs without care for speed, so some of them were closer to 16-minute mile averages, some were around 15-minute mile averages for the entire run, and the day I ran the full marathon course for training I ended up doing 16+ minute miles and felt fabulous at the end.

I ended up doing a few “faster” “shorter” long runs (on my cutback weeks), where I would do a half marathon-ish distance on the actual marathon course (a public trail), and try to go faster than my super slow long run pace. I had several successful runs where I was at or near marathon pace (which for me would be around 13m30s). So yes, you can train slow and run fast for a marathon, even without much speed work, and even if you are doing a run-walk method, and even if you’re as slow as I am. Running ~15-minute miles took forever but kept my feet and body healthy and happy through marathon training, and I was still able to achieve my sub-6 hour marathon goal (running 13:41 average pace for 26.2+ miles) on race day.

Now let’s talk about fueling, and in particular fueling for people with type 1 diabetes and for people wondering if the internet is right about what fueling requirements are for marathon runners.

I previously wrote (for a T1D audience) about running when fasted, because then you don’t have to deal with insulin on board at the start of a run. That’s one approach, and another approach is to have a smaller meal or snack with fewer carbs before the run, and time your run so that you don’t need to bolus or inject for that meal before you start your run. That’s what I chose for most of my marathon training, especially for longer runs.

On a typical non-running day, I would eat breakfast (½ cup pecans, ¼ cup cranberries, and a few sticks of cheese), my OpenAPS rig would take care of insulin dosing (or I could bolus for it myself), and my BGs would be well managed. However, that would mean I had a lot of insulin on board (IOB) if I tried to run within an hour of that. So instead, during marathon training, I ended up experimenting with eating a smaller amount of pecans (¼ cup) and no cranberries, not bolusing or letting OpenAPS bolus, and running an hour later. I had a small BG rise from the protein (e.g. would go from 100 mg/dL flat overnight to 120-130 mg/dL), and then running would balance out the rest of it.

I generally would choose to target my blood sugar to 130 mg/dL at the start of long runs, because I prefer to have a little bit of buffer for if/when my blood sugar began to drop. I also figured out that if I wasn’t having IOB from breakfast, I did not need to reduce my insulin much in advance of the run, but do it during the duration of the run. Therefore, I would set a higher temporary target in my OpenAPS rig, and if I was doing things manually, I would set a temporary basal rate on my insulin pump to about ⅓ of my usual hourly rate for the duration of the run. That worked well because by the time the beginning of my run (30-45 minutes) brought my BG down a little bit from the start with the protein breakfast bump (up to 130 mg/dL or so), that’d also be when the reduced insulin effect would be noticeable, and I would generally stay flat instead of having a drop at the beginning or first hour of my run.

After my first hour or so, I just kept an eye periodically on my blood sugars. My rule of thumb was that if my BG drifted down below 120 mg/dL, I would eat a small amount of carbs. My carb of choice was an individually wrapped peppermint (I stuffed a bunch in my pocket for the run) that was 3-4g of carb. If I kept drifting down or hadn’t come back up to 120 mg/dL 10-15 minutes later, I would do another. Obviously, if I was dropping fast I would do more, but 75% of the time I only needed one peppermint (3-4g of carb) to pause a drift down. If you have a lot of insulin on board, it would take more carbs, but my method of not having IOB at the start of long runs worked well for me. Sometimes, I would run my entire long run with no carbs and no fuel (other than water, and eventually electrolyte pills). Part of this is likely due to the fact that I was run-walking at such low intensity (remember 15-ish minute miles), but part of this is also due to figuring out the right amount of insulin I needed for endurance running and making sure I didn’t have excess insulin on board. On my faster runs (my half marathon distance fast training runs, that were 2+ minutes/mile faster than my slow long runs) and my marathon itself, I ended up needing more carbs than a super slow run – but it ended up being about 30 grams of carbohydrate TOTAL.

Why am I emphasizing this?

Well, the internet says (and most coaches, training plans, etc) that you need 30g of carbs PER HOUR. And that you need to train your stomach to tolerate that many carbs, because your muscles and brain need it. And without that much fuel, you will ‘hit the wall’.

My hypothesis, which may be nuanced by having type 1 diabetes and wearing a CGM and being able to track my data closely and manage it not only by carbs but also titrating insulin levels (which someone without diabetes obviously can’t do), is that you don’t necessarily need that many carbs, even for endurance running or marathon running.

I’m wondering if there’s a correlation between people who max out their long runs around 16-20 miles and who then “hit the wall” around mile 20 of a marathon. Perhaps some of it is muscle fatigue because they haven’t trained for the distance and some of it is psychological of feeling the brain fatigue.

During my marathon, in which I ran 2+ min/mi faster than most of my training runs, I did not ever experience hypoglycemia, and I did not “hit the wall”. Everything hurt, but I didn’t “hit the wall” as most people talk about. Those might be related, or it might be influenced by the fact that I had done a 20, 22, 24, 26, and another 21 mile run as part of my training, so my legs were “used” to the 20+ mile distance?

So again – some of my decreased fueling needs may be because I was already reducing my insulin and balancing my blood sugars (really well), and if my blood sugar was low (hypoglycemia), I would’ve needed more carbs. Or you can argue my lower fueling needs are because I’m so slow (15-16 minute mile training runs, or a 13m40s marathon pace). But in any case, I wanted to point out that if the fueling advice you’re getting or reading online seems like it’s “too much” per hour, there are people who are successful in hitting their time goals and don’t hit the wall on lower fueling amounts, too. You don’t necessarily have to fuel for the sake of fueling.

Note that I am not doing “low carb” or “keto” or anything particular diet-wise (other than eating gluten-free, because I also have celiac disease) outside of my running fuel choices. This was a successful strategy for me, and I eat what might be considered a moderate carb diet outside of running fuel choices.

Ps – if you don’t fuel (carbs or other nutrients) during your runs, don’t forget about your electrolytes. I decided to keep drinking water out of a Camelbak in a running pack, rather than filling it with Gatorade or a similar electrolyte drink, but I’m pretty electrolyte sensitive so I needed to do something to replace them. I got electrolyte pills and would take them every 30 minutes or so on long training runs when it was hotter. Play around with timing on those: if you don’t sweat a lot or aren’t a salty sweater, you may not need as many as often. I ended up doing the bulk of my long runs on hot days, and I sweat a lot, so every 30 minutes was about right for me. On cooler runs, one per hour was sufficient for me. (I tried these chewable tabs in lemon-lime but didn’t like the salt feeling directly in my mouth; I ended up buying these to swallow instead: I didn’t have any digestion issues or side effects from them, and they successfully kept my electrolytes to manageable levels. The package says not to take more than 10 within a 24 hour period, but I ended up taking 12 for my longest training run and the marathon itself and suffered no ill effects. It’s probably set to max 10 because of the amount of salt compared to the typical daily amount needed..but obviously, if you’re doing endurance running you need more than the daily amount of salt you would need on a regular day. But I’m not a doctor and this isn’t medical advice, of course – I’m just telling you what I chose to do).

In terms of training, here’s everything the internet told me to do for marathon training and everything I did “wrong” according to the typical advice:

  • Your long run should be 20-30% of your overall weekly mileage

    What I did: Sometimes my long runs got up to 70% of my weekly mileage, because I was only running 3 and then 4 days a week, and not doing very long mid-week runs.

  • Have longer mid-week runs, and build those up in addition to your true long run

    What I did: I did build up to a few 5-6 mile mid-week runs, but I chose consistency of my 4 runs per week rather than overdoing it with mid-week medium runs

  • Run 5-6 days a week

    What I did: Only run 4 times a week, because I wanted a rest day after each run, and wanted a rest day prior to my longest run. I ran Monday, Wednesday, Friday, then added Saturday short runs. Monday was my long run (because I have the benefit of a flexible schedule for work).

  • Get high mileage (start from a base of 30-40 miles a week and build up to 50-60 miles!)

    What I did: I started with a “base” of 10 miles a week with two runs that I was very proud of. I went to three runs a week, and then 4. My biggest running week during training was 40.55 miles, although they were all 20+ mile weeks (long or cutback weeks) after the first two months of training.

  • Do progressively longer long runs for two or three weeks in a row and then do one cutback week, then continue the progression

    What I did: Because of the time on my feet cost of being a slower runner, I did an every-other-week long-run progression alternating with a shorter cutback week.

  • Long run, tempo run, speed work, etc. plus easy runs! All the things each week!

    What I did: a long run per week, then the rest of my runs were usually easy runs. I tried a handful of times to do some “speed” work, but I often time was trying to keep my feet from being injured and it felt like running faster caused my feet to be sore or have other niggles in my legs, so I didn’t do much of that, other than doing some “cutback” long runs (around half marathon distance, as well as my last 21-mile run) at close to marathon pace to get a feel for how it felt to run at that pace for longer.

TLDR, again:

I signed up for a marathon in fall 2018 planning to run it in July 2019 but was thwarted by a broken ankle in January 2019 and COVID-19(/20) for 2020, so I ultimately trained for and ran it in July 2021. I am a slow runner, and I was able to achieve my sub-6 hour marathon goal using run-walk and without causing additional injury to my feet. And, because of my “slow” or less intense running, I needed a lot less fuel than is typically recommended for marathoners, and still managed my blood glucose levels within my ideal target ranges despite 5, 6, and even 7 hours run on my feet. Yes, you can run marathons with type 1 diabetes. And yes, you can run any length endurance runs with type 1 diabetes!