QUIET RED FLAGS OF UNDEREATING
(This post is not medical advice and is not an exhaustive list of how a prolonged energy deficit presents itself.)
If we picture that our bodies have a budget to adhere to, it makes sense that we can only spend the money (or, in this case, energy) that we have. And that if we are stretching that funding a little bit too much, resources start to get a bit strained – because the energy we get from food doesn’t just fuel workouts or determine if our weight goes up and down, it also keeps us alive. The energy we consume via calories does a little bit of everything: maintains body temperature, keeps your heart beating, supports our brains, produces hormones, digests food, maintains and repairs tissues, supports our immune systems, recovers from exercise, and countless other things that happen behind the scenes while you're sitting here reading this.
And then on top of all the things it does to support us (literally) living, we ask it to do other things so that we can be human, too: walk the dog, chase the kids, focus for meeting after meeting, lift weights, work, clean the house, carry groceries…ya know, life.
But back to the budget: when there is energy available, our bodies have resources to spread around – kind of like having a credit card and a bank account that can support paying it off each month. But when there consistently isn’t enough energy – when we know that every penny of a paycheck needs to go somewhere, and even then it might not cover all of our expenses – our bodies have to get a little more selective.
Our brains don’t sit down with a spreadsheet and decide that hair growth is getting a 15% cut this quarter. But over time, it has to cut resources to systems and processes that aren’t immediately necessary for and essential to survival. So let’s talk about some of these quiet red flags, or “budget cuts,” that come up when we’re undereating.
1 | YOU FEEL LIKE YOU’RE LIVING IN THE FREEZER
Some people simply run cold. But if feeling cold is new or has become increasingly worse (especially while dieting or losing weight), it might not just be a personality trait. (This could look like wearing, and feeling comfortable in, a sweatshirt, when everyone else is in a t-shirt, or having hands and feet that are always cold.)
Our bodies use energy to generate and maintain heat, and with prolonged energy restriction, the body can make metabolic and hormonal adaptations that reduce energy expenditure and heat production. If the energy budget is tight, feeling delightfully comfortable temperature-wise isn’t the top priority.
2 | YOU SLEEP HAS GOTTEN WEIRD
This one can feel counterintuitive, because if we’re feeling exhausted, we should sleep great, right?! Except maybe you don’t. Maybe you have trouble falling asleep, maybe it’s staying asleep (waking frequently), maybe it’s feeling wiiiide awake at 2am. It could be that you technically spend enough hours in bed, but your sleep doesn’t feel restorative.
Sleep disturbances have many possible causes, so waking up one Tuesday night doesn’t mean you’re not eating enough, but inadequate energy intake (especially when paired with high training demands) can contribute to disruptions in sleep – our bodies can be tired and not in a particularly great state to be able to focus on rest.
3 | DIGESTION HAS SLOWED
Let’s get into “TMI” territory: you’re constipated, you’re going less frequently than usual, meals sit heavily, you feel bloated even after small meals.
Yes, it could be a specific ingredient – many times our first instinct is to start elimination diets to remove a food or food group that seems triggering. But sometimes eating less in an attempt to “fix” digestion that’s already sluggish compounds the problem. Lower food intake can mean less total food volume, and prolonged inadequate intake can also alter gastrointestinal motility (our GI tract slows down muscle contractions when there isn’t sufficient food volume to support more regular ones).
4 | YOU’RE NOT RECOVERING LIKE YOU USED TO
Exercise is a stressor – that’s not inherently bad! Stress is actually the whole point: when we apply a training stimulus, we recover from it, adapt, and ideally become stronger/faster/more capable in accepting that stimulus. The adaptation here comes from the recovery, and recovery requires resources, which means we can’t ask our bodies to be building while giving it fewer building materials.
The quiet red flags in recovery often look like: workouts feeling harder (even if they are similar workouts to your usual), soreness that persists, performance plateaus (or regressions), or little aches and pains appearing more frequently.
5 | HAIR SHEDDING
Hair naturally cycles through periods of growth and shedding, and there are many reasons someone might experience increased hair loss: hormonal changes, illness, major stress, certain medications, nutrient deficiencies, postpartum changes, and other medical causes.
And inadequate energy and nutrient intake can disrupt normal hair growth cycles. Hair growth (and styling, too) may feel important to us, but from our body’s perspective, growing a luxurious head of hair is somewhat less urgent than, say, keeping our hearts beating, and if resources are chronically limited, hair growth can take a back seat.
Please note that unusual or persistent hair loss is worth discussing with your healthcare provider.
6 | CHANGES IN MENSTRUAL CYCLE
Longer cycles, irregular cycles, significantly lighter flows, or complete disappearance of a menstrual cycle are not normal or inevitable consequences of “being fit.”
Ladies: our reproductive cycles require adequate energy availability. When energy becomes chronically low, the body can alter hormonal signaling between the brain and the reproductive system, and ovulation and menstruation may be disrupted as a result.
I get it…losing a period might seem “convenient” (no tampons! no cramps! no surprise period while you’re wearing white pants on vacation!). However, a missing period due to inadequate energy availability isn’t a fitness achievement.
Menstrual changes can happen for many reasons, including pregnancy, breastfeeding, contraception, perimenopause, PMOS, thyroid conditions, stress, and other medical issues. Changes warrant a conversation with your healthcare provider.
7 | YOU’RE GETTING SICK OR INJURED MORE OFTEN
Small injuries popping up more frequently, picking up every cold that makes its way to your house, things taking longer to heal, recurring bone or stress injuries – none of these are an automatic indication of needing more calories. And yet, your immune system, bone remodeling, tissue repair, and recovery all require energy, and these systems can be affected by undereating, too.
None of these red flags exist in a vacuum – think of these as clues, not diagnoses. Often we need to get curious about the collection of information that our bodies are giving us rather than individual symptoms.
Underfueling can happen without looking extreme. You don’t have to be eating an objectively small amount of food, look a certain way, be an elite athlete, intentionally restrict, or have an eating disorder. It could be that you increased your training without increasing your intake, have been dieting for an extended period of time, have a schedule that makes regular eating difficult, or have shifted your eating habits in a way that’s removed calorie-dense foods. Underfueling is ultimately a mismatch between the energy you’re taking in and the energy your body needs.
SO: DON’T WAIT FOR YOUR BODY TO START YELLING
Undereating doesn’t always present itself as a grumbling stomach. More often it presents as (seemingly) smaller symptoms that feel easy to brush off (and a lot of these symptoms have causes other than nutrition). But when several start happening together – particularly if prolonged intentional dieting, weight loss, or high levels of activity are also part of the picture – it may be worth considering whether your body is consistently getting enough energy.
Sometimes the information that our bodies provide when it is starting to make budget cuts is subtle, and it can be beneficial for us to pay attention while these signs are still a whisper.
YOUR NEXT STEP
Does this blog post resonate with you? At Front Porch Nutrition, I coach real people through real-life nutrition — thinking through what your wants, needs, and goals are, and working together to make changes that last not just in the moment, but for the long haul. Get started with 1:1 nutrition coaching today!
