One of the most common issues many people run into during dieting is constipation, which is defined by the Mayo clinic as having fewer than three bowel movements a week with accompanying straining, discomfort and/or hard stools. 

Unfortunately, many are too embarrassed to bring up the issue or they just accept it as part of the process as on the surface, it does make sense. You’re eating less food therefore digestion slows down, meaning constipation is normal right?

Well, yes and no. You are eating less calories, and there is going to be some slowdown towards the end if your calories do have to get quite low, but if you’re suffering from constipation and you’re not in the final 4-6 weeks of your transformation, then you’re just simply doing things wrong.

The goal of this article is to help you keep your digestion humming along without resorting to fibre supplements, slimming teas or even worse, laxatives. Yes, there will be times when they may need to be used but they should be LAST resorts after you have exhausted the below tips and seeked advice from your medical provider to rule out any other underlying pathology.

With that disclaimer out of the way, let’s dive in!

Food Volume & Fibre

Interestingly, the same high volume, nutrient dense foods that help keep you satiated are also the best foods to promote healthy digestion and movement throughout the intestines. Remember, the lining of our stomach has mechanoreceptors that detect distention due to the volume of food, independent of calories. This is one of the reasons why consuming 1000 calories worth of broccoli (~3kg) is virtually impossible while doing the same with cookies (150-200g) is childsplay. 

In this study, the researchers gave the subjects either a mushroom or beef based meal where the volume (or weight) of the meal was held constant meaning if they consumed 250g of beef, they would then consume 250g of mushrooms. They did a week of the beef based lunches and another week with the mushroom based lunches and found no difference in satiety despite the beef eating group consuming ~400 calories more.

By eating more high volume, nutrient dense foods, you are able to eat higher amounts of food while still keeping calories low. We know that water and fibre are big players when it comes to helping with constipation and there is no reason they cannot stay high throughout a hard diet.

I plugged in a sample diet for a 55-60kg individual who is really pushing hard towards the end of their fat loss phase. Despite the calories being ~1200, I was still able to keep fibre at over 40g per day while still protein target recommendations. Yes, the fats are a little low but due to it being a short term push along with just how micronutrient rich the diet still is, it’s not a concern at all.

The total weight of the food should also be noted here which is very important. By consuming over 2kg worth of food (which would be higher when foods like oats and lentils are mixed with water) you are encouraging the gastrointestinal system to continue working hard vs coming to a complete halt which happens all too frequently when calories get low.

Additionally, by incorporating a similar menu to the example you may experience a higher rate of energy expenditure due to the thermic effect of eating (the energy our body uses to digest and assimilate food) when compared to someone following a low fibre, low nutrient dense diet despite the calories being the same. 

This very recent 12 week study compared two energy matched diets (25% deficit) with one being of “higher quality” that contained more fibre, plant protein, monounsaturated and polyunsaturated fats, the other being of “lower quality” that contain more saturated fats and simple sugars. The results showed an average loss of ~2kg more in the higher quality diet group, despite calories (reported) staying the same.

Unfortunately, protein wasn’t matched exactly (20g more in the higher quality group) but that alone doesn’t explain the large difference in results. We know that nutritional research is prone to misreporting but even if the subjects did misreport, the result still shows more weight loss in the “higher quality” group. This could be down to feeling fuller for longer, less cravings and potentially higher energy levels leading to better exercise performance or being more active in general.

Either way, a high volume, nutrient dense diet should definitely be the core for anyone looking to diet successfully especially when calories get low. On top of that, it helps keep you regular without the need of additional supplements or biohacking your rectum by putting coffee up there!

Circadian Alignment

We have previously discussed the importance of circadian rhythms when it comes to our overall health but it’s implications for improving your digestion is extremely underrated.

As with every system in our body, our digestion follows a certain circadian rhythm where various aspects of the intestinal tract are more active than others. In healthy adults with a regular sleep/wake cycle, the colon is known to contract three times harder in the first few hours of the morning in comparison to the evening where activity is naturally very low. This is the main reason as to why we are more inclined to have a bowel movement in the morning and not in the evening.

Knowing this, we can use this natural occurence to our advantage by making sure we give ourselves enough time in the morning to go. Many of us don’t think about this but if you feel rushed in the morning, the likelihood of you missing this “prime time” is very high, leading to a feeling of constipation throughout the day due to having to commute to work, sit at a desk most of the time and be around other people. A horrible combination for our bowels.

If you feel this is something you struggle with, try incorporating this morning routine.

• Wake up half an hour earlier than usual.
• Consume between 500-750ml of lukewarm water with a pinch of salt and squeeze of a lemon.
• Have a strong black coffee (if tolerance allows) or black tea.
• Go for a brisk walk.

The combination of the warm liquids, caffeine, lemon and salt can really stimulate the digestive tract to contract even harder and encourage movement of waste through the system while the walking amplifies this effect even more.

Keep A Consistent Meal Schedule

Our body thrives on routine and one of the easiest ways to improve your digestion is to keep a regular meal schedule each day, with around 3-4 hours in between your meals if eating 3-4 meals a day which is what we typically recommend for most.

When we eat at regular times, we entrain our body to expect nutrients at specific times meaning we start producing the necessary hormones in anticipation of our next meal. Ever wondered why you tend to get hungry at the same time each day? This is one of those hormones (ghrelin) upregulating as your stomach prepares for the expected meal.

Another important variable to keep in mind is the spacing of your meals which is often overlooked, especially in those who are intermittent fasting and trying to pack all their calories within a 6-8 hour eating period. 

After each meal, our digestive system has an in-built “sweeping mechanism” that comes in to move things along in a timely manner. It is called the “migrating motor complex” and can only come into action during periods of fasting meaning if you are constantly grazing/snacking every couple of hours, you are not letting this system do its job effectively between meals leading to sluggish digestion.

The migrating motor complex seems to activate ~1.5-2 hours after your last meal and requires around 1-1.5 hours to do its job effectively which is where the 3-4 hour recommendation between meals comes from. 

Get Enough Light

This paper looked at the digestion of an evening meal when the subjects were either placed in a dimly lit room or a brightly lit room for 9 hours (7:00am-3:00pm). The researchers discovered a significant difference in how effectively that meal was digested between the groups. When exposed to bright light for the majority of the day, the individuals experienced far better carbohydrate assimilation while the dimly lit group experienced far more malabsorption, leading to bloating and discomfort. 

For those who work inside all day, it’s highly recommended you do your best to get outside for at least 30-60 minutes, ideally between 10:00am-2:00pm. 

Post Workout Nutrition

Exercise in general has been shown to be associated with better digestion but the intensity and modality definitely plays a part here. With very intense exercise, stress hormones rise and divert blood from the intestines and direct it towards the extremities, leaving the stomach in a relatively vulnerable state temporarily. 

It has been shown that in healthy individuals, intestinal permeability* increases with moderate to intense cardiovascular exercise lasting from as early as 10 minutes into the session, leading to poorer nutrient absorption and overall digestive capacity. There hasn’t been as much research on resistance training, but I would say there would be a lot of similarities, especially when training hard.

We recommend waiting at least 30-60 minutes after an exercise session along with practising some deep breathing before consuming your next meal. By shifting from a “fight or flight” state into a “rest and digest’ state, you will be able to digest your food a lot more effectively.

If this isn’t possible, a simple protein shake with some fruit would be a good option due to the ease of absorption. 

*Intestinal permeability refers to how easily substances pass through the intestinal wall. When the tight junctions of intestinal walls become loose, the gut becomes more permeable, which may allow bacteria and toxins to pass from the gut into the bloodstream. This phenomenon is commonly referred to as “leaky gut.

Walk More

One of the best things you can do to improve your gut health is to simply walk more. We have been huge fans of steps in helping people achieve their body composition goals but many do not realise just how profoundly it can impact your digestion.

Because walking is done at such a low intensity, we do not run into the same digestive issues that can potentially come with hard exercise. Even though your arms and legs are moving, there is still ample blood flow happening through your intestines and with every step, smaller muscles throughout the abdomen and lower back are contracting and helping things “move along the pipeline” so to speak. 

Being sedentary is one of the worst things you can do with your digestion so make a conscious effort to get moving. A really simple trick is to pair your walks with the period of when your digestive system is the most active. This is first thing in the morning (as mentioned earlier) and after each main meal.

We understand that not everyone can get up and go for a walk after each meal but if you can, definitely make the most of it. A 10-20 minute walk is all that is needed and on top of that, you will also be improving your blood glucose control.

Manage Your Stress

The gut and the brain are inextricably linked yet many seem to forget this when they run into digestive issues. All the tips we have discussed so far are more physical solutions and in fact, should vastly improve things for many of you reading but understanding the impact stress can have on your gastrointestinal health is critical.

One in five people suffer from Irritable Bowel Syndrome (IBS) which at this point in time, has no cure and is known to be exacerbated by stress. Fundamentally, many medical professionals prescribe lifestyle habits such as meditation, gratitude journaling and engaging in relaxing activities. 

When we are dieting and pushing the envelope with fat loss, it’s safe to say that our system can feel quite stressed at times meaning it can also be causing a lot of digestive problems. Depending on the individual, this could manifest as diarrhoea or constipation but either way, stress management techniques should not be overlooked.

Engage in fun activities, do something that gets you into a meditative state (that isn’t hard exercise), talk to your friends, go for walks and prioritise your sleep. 

Wrapping Up

To summarise, if you are struggling with constipation throughout your diet you’re going to be doing yourself a world of good by focussing on the aspects discussed above.

Prioritise high volume, high fibre, nutrient rich foods. For 1200 calories, you could consume close to 45g of fibre per day and 2-2.5kg worth of food.

Align your circadian rhythm with a strong sleep/wake schedule and light exposure throughout the day.

Use the morning routine to take advantage of that “prime time” for elimination.

Walk more, especially after meals if you can.

Engage in fun activities that really relax you, a healthy mind is a healthy gut!