Negative Effects of Under-eating
Some interesting facts on undereating and chronic dieting.
Listen, guys, this is so freaking common, the number of women I meet and work with who, once I get them to log their food for an entire week are undereating is astonishing! Most of the time they are not even ‘underweight’, in fact, most of the time they are carrying a lot more extra body fat than they would like. Weird right?! Have we not been told calories in vs calories out = weight loss? Well yes, this does work but only if you have had a chance to reverse your diet back up to at least your maintenance calories! So let's take a look below and talk about what calories are, and what happens to your physiology, mental health, and waistline when we try to continuously eat in a deficit.
Calories are units of energy we get from food. Everybody has different needs regarding caloric intake to either gain, maintain or lose body ‘mass’. For the sake of this post, I may use ‘body fat’ or ‘weight’ interchangeably. The brain and internal organs need a specific amount of calories to function. Individual needs vary depending on body weight, height, age, exercise, and metabolic rate. For this post, I will use a very quick and simple way to figure out the absolute lowest amount of calories you should be eating in a day. So for example let’s take me: body weight 151 lb on average. If we take my body weight and multiply it by 10, we get the lowest calories I should be eating (1,510). How many times have you logged onto my fitness pal and it’s suggested 1,200cals? This means for me to to just exist without any exercise, I need around 1,500 calories to get through a day. Now we have to factor in my energy output. We need to add 300-500 calories per day to account for all the steps and workouts I do. This could bring me up to 1,800-2,000 for me to sustain my current body weight of 151lb. Do you see how this works?
So how many of you are undereating?
Are you eating close to your lowest calorie needs?
Have you been doing this for some time plus cardio and weights and not seeing any changes?
Below are some symptoms that can arise from chronic dieting/undereating and the neurochemical and physiological changes that can occur.
Mood and personality can be highly affected by undereating. When you deprive your brain of energy it goes into survival mode which causes the higher functioning areas of the brain such as the cortex to slow down. This relates to consciousness, logical reasoning, and the ability to make decisions. This lack of cognitive function can leave you less resilient to stress and unable to relax. What does this sound like? Brain fog and anxiety. Depression and anxiety can increase, as well as irritability and bouts of anger. Overall anxiety and panic attacks can also increase. This can be related to hypoglycemia or low blood sugar which can increase HR and shakiness tricking the mind into anxiousness and panic. The brain requires blood sugar to function optimally, when this drops, your ability to exert self-control also drops. Not providing enough fuel for your brain causes negative mood and personality changes, it can also create an obsessive way of thinking about food, it can be all-consuming where you stop eating certain foods ( for example demonizing carbohydrates or fats), you may withdraw from social events, this can have a huge impact on how you view yourself and how you interact in relationships.
You’re not losing body fat. This is often the case when individuals undereat and overexercise, especially with a low carbohydrate diet. Let me clarify, a short-term deficit of around 300-500 calories can prove effective, but we are talking chronic, long-term larger deficits. The bigger the deficit for longer periods will change your metabolic rate. Drastic changes in diet for long periods can reduce the function of your thyroid, adrenals, and sex hormones to reduce the overall energy output. When thyroid functions are reduced, sex hormones are shut down and the rising stress hormone cortisol is released. Chronically elevated cortisol leads to both leptin and insulin resistance which often appears as having a higher body weight. Think inflammation, puffy, bloated, extra body fat around the midsection, hips, and thighs.
Low-calorie diets paired with low body fat can be detrimental to women of childbearing age. Undereating and being too lean can have a very negative impact on your ability to conceive. Oftentimes this can cause infertility as well as amenorrhea ( loss of a period) called hypothalamic amenorrhea. This is caused by chronic caloric deprivation and is associated with physiological changes such as the hypothalamic-pituitary-adrenal (HPA) axis over activity. This is sometimes called adrenal fatigue and is associated with overall exhaustion and loss of a period.
Hypoglycemia or low blood sugar as I mentioned earlier is another side effect of undereating.
Common symptoms are hunger, shakiness, anxiety, dizziness, sweating, weakness, confusion, and changes in mood(hangry). When these symptoms occur we often reach for quick simple carbohydrates full of sugar to feel better which now spikes the blood sugar. Fluctuations in blood sugar often lead to the cycle of binging. Letting blood sugar drop too low and then binging on sugary goodness.
Sleep can also be negatively affected by undereating. Eating adequate calories can improve the quality and duration of sleep you get. Increasing carbohydrate intake can lead to falling asleep faster, staying asleep longer, and overall better blood sugar management. This is important because while we sleep our blood sugar drops and the liver releases stored glucose to keep it steady. If you are constantly under eating and overexercising there won't be enough glucose stored in the liver to keep blood sugar level. The body ends up releasing stress hormones such as cortisol and adrenaline to promote glucogenesis ( creating new glucose). When these hormones elevate they often lead to wakefulness during the night. I know there are some of you wondering why you constantly wake up at 2 a.m. for no reason. Try having a small snack before bed, a carb and fat pairing is totally fine such as a banana and tbsp of nut butter.
Losing hair, constipation and chronically being cold are other symptoms that may arise. A lack of calories, protein, or both can lead to hormone changes that affect your hair. A drop in sex hormones progesterone, estrogen, and testosterone can lead to hypothyroidism caused by long-term dieting.
So, ladies. Check yourselves; take note of your mood, sex drive, energy levels, brain function, hormone cycles, and sleep, and assess your nutrition. Could you potentially heal your mind body and soul just by changing how you eat?? Everything is connected. Fuel your body, mind, and soul with whole foods and enough calories for your specific energy needs. Always refeed for a good amount of time before you cut calories. Stop depriving yourself of precious fuel and get your body functioning back up at 100%.