WHY and HOW Disordered Eating Causes Harm Part 1: Under-eating

(IF you didn’t have a chance to check out my previous post on WHAT disordered eating IS, you may want to go back and read it here.)

People are often surprised to learn about the idea of "disordered eating"; a common, yet well-disguised, issue that affects a large segment of the American population.  One may start to wonder what they can DO once becoming aware of just how pervasive it is.

If you, or someone you love, falls into the category of a “disordered eater” what happens next?

The next step is understanding WHY and HOW is it harmful.

Simply said: restrictive, externally motivated, and weight-loss-focused behaviors often cause physical, mental, and emotional health problems.

(When I talk about “health” I am referring to all THREE aspects of a individual. Health is more than just physical well-being)

Today’s post will cover the most common culprit I see in my practice.  It occurs in dieters and non-dieters alike, and it affects people who are doing it consciously and unconsciously. The issue is under-eating.


Under-eating is: eating less than your body needs, desires, or requires. This can be measured by calories and/or carbohydrates consumed, your hunger signals, or an overall sense of bodily satisfaction.


I want to be very clear that under-eating is NOT starving yourself, as in anorexia nervosa or a fast. It is simply under-eating. It is very common in our modern weight-centered society (especially in busy, body-aware women/mothers) and I think it's partly because many of us have a skewed sense of how much food we actually need in a day, especially if we are active.

One of the best studies that details just how damaging under-eating can be is the “Minnesota Starvation Experiment”. They use the term “starvation” but the men were eating, on average about 1700 calories a day. Yep, 1700 calories. It’s worth a read because it forms a lot of what we understand today about the psychological and mental effects of food restriction.


So what are the effects of under-eating???


Potential risks of under-eating include, but are not limited to:

·         Poor quality sleep: trouble falling asleep or trouble staying asleep

·         Daytime fatigue (reliant on coffee or caffeine)

·         Loss of interest in sex or physical touch

·         Changes in menstrual cycles for women; decreased fertility for both genders

·         Increased cravings (usually for carbs and sugar… hmm hello ‘sugar addiction’??)

·         Low blood pressure

·         Feeling cold all the time

·         Irregular heartbeat (may feel like a panic attack)

·         More anxiety in general (caffeine will make this worse and is often abused in under-eaters, as stated above)

·         HEADACHES (if you are prone to migraines under-eating is a HUGE trigger)

·         Trouble paying attention or concentrating

·         Irritability (hello, HANGRY!) Nope, you are not a raging witch, you are just hungry.

·         Increased obsession/preoccupation with food

·         Ironically, “feeling fat”. Officially termed “body dissatisfaction”, the more you under-eat (diet) the more obsessed with weight/body you become. You may start to “feel fatter” even if you are losing weight or maintaining your current weight.

·         Speaking of weight, undereating often causes weight GAIN, especially in the midsection. This can be from actual fat storage or retaining of water.

·         Depression resulting from the psychological damage dieting creates OR it can be from the physical malnourishment of your brain. Or both.


But the biggest way I have seen undereating affect my body is in my gut. My digestive track has taken the brunt of my disordered eating ways.

I recently attended a conference where Marci Evans, RD spoke about this exact topic. She reviewed the research being done with clinical eating disorder patients relating to gut health, but it’s fair to assume that some, if not the majority, of the findings will translate in some way to disordered eaters as well (aka dieter and under-eaters).

A few key points from her presentation:

- 98% of eating disorder patients have some sort of functional gut disorder

- Restriction of food results in delayed gastric emptying and/or premature fullness

- Lack of regular food intake can result in constipation (due to the lack of bulk and/or the lack of the “signal to go”)

- Anxiety (especially around food or body) can result in increased gastric pressure (i.e. bloating)

- Increased IBS type symptoms are directly related to poor body image… which often leads to dieting… and starts the vicious cycle all over again


Under-eating is just one type of disordered eating behavior that comes with REAL and significant consequences. It’s beyond the idea that “diets don’t work”... yes that is true for long-term weight loss, but what about the more immediate, day-to-day effects? Not only does under-eating NOT create lasting bodily changes, it causes harm in the present moment.


Keep an eye out for my next topic:

The SCALE. Does weighing yourself help or harm?