WEIGHTY MISTAKES: are you under-eating and/or overexercising ruining your metabolism?

By Kate Skinner from Nutrition By Nature.

“One of the greatest hindrances to the achievement of great health and vitality is the widespread notion that we should exercise as much as possible and eat as little as possible” Matt Stone, obesity researcher & health writer

When weight loss is a goal, most people tend to assume they must cut their food intake and drastically step up the exercise regime. Their portions dwindle and stretches between meals become longer, whilst they increasingly push harder and for longer at the gym in the hope of obtaining desired fat-loss. On top of this, they may dip their toes into the murky pool of fad diets, succumbing to the lures and promises of various regimes (vegetarian, macrobiotic, raw foods, superfood, primal, paleo, food combining, fasting, Atkins, Dukan… the list goes on).

When this type of behaviour repeats itself time and time again, as is commonly the case with your average yo-yo dieter, weight loss does not tend to be a lasting consequence even when it is the sole goal of such pursuits. Instead, it’s more likely that dieters end up looking and feeling worse: tired, irritable, bloated, constipated, food phobic, frustrated, unsure of what’s left to eat, and unsure of which way of eating or exercising to turn to next in the name of good health. But this time around, in worse shape, with a growing list of digestive and metabolic ailments that weren’t there before, perhaps a few food sensitivities and nutrient deficiencies now forming, lots of weird cravings and food hang-ups, maybe some hyper or hypoglycaemic issues, sleep troubles, a bit of bone loss, lack of sex drive, thinning hair and wacky menstrual cycles… dieting will do that to you. Chronic dieting will also leave you with a metabolism that’s so damaged that it no longer responds to drastic under-eating and/or over-exercising, and a body that has aged at a vastly accelerated rate.

More than 80% of people on diets will regain the weight they lose, plus more.Eating any overly restricted diet is the quickest way to ruin your heath and start shutting down your entire system. Prolonged dieting sends your body into a state of stress (starvation) and inhibits thyroid function, and the thyroid gland is the master of pretty much all your bodily systems –  it is in charge of regulating metabolism and plays a major role in the production and function of hormones, enzymes, antibodies, neurotransmitters, energy and energy stores. Not only will it damage your metabolism, but excessive dieting can also increase a hunger hormone called ghrelin, and promote resistance against the function of the fullness hormone leptin, leaving you hungrier and less satiated overall. During a period of underfeeding, your cells start to prime themselves for when you do eat food, so that they can store fat better than ever before, more efficiently and more quickly than when your food energy intake was much higher. This happens particularly in the abdominal region (making it easier to gain weight in this region during and post-undereating) as fat stores in this area act as a reservoir of energy for vital organ function.

Popular diets and high-impact exercise programs emphasize ways to use up more energy and chemicals than you rebuild. This will cause you to lose weight for a short period of time, but most of the weight loss is due to breaking down cell structures, organ tissue, and muscle and bone tissue, along with fat loss. In essence, you are overstressing and starving your body, forcing it to consume itself to keep you functioning. At the same time your metabolic rate is adjusting to the under-eating and over-exercising and getting steadily lower in order to conserve energy and body tissues, which, as mentioned, won’t stand you in good stead in the long run if the diet suddenly ends and normal eating and/or exercising resume.

When it comes to exercise, much of the common cardiovascular-style exercise that people do can actually do more harm than good. This style of exercise iscatabolic, that is it “breaks down” tissues and uses up nutrient stores in the body, rather than “building up” lean muscle mass via anabolic activity. You may end up losing weight but at the expense of your function and structure, causing damage to your metabolism. Therefore, the more you over-exercise to lose weight, the more you will have to exercise to keep it off because of the drop in both metabolic rate and lean body tissue. Coupled with under-eating and/or extreme dieting, it’s a recipe for metabolic disaster.

You need to be healthy to lose weight, not lose weight to be healthy.

The key is to realize that weight loss plays second fiddle to regenerating overall health and a properly functioning metabolism, not the other way around. It’s all too easy to get caught up in the desire for quick results in a culture of instant gratification, but health doesn’t work like that. Maintaining an ideal weight (a balanced amount of lean body tissue and a normal amount of protective fat) is a natural consequence of good health, adequate nutrition, a working metabolism and a balanced endocrine system.

Food is so misunderstood. Many people seem to think, to the detriment of both their bodies and their quality of life, that food is a necessary evil and the less you eat of it the better. These people are skipping meals, starving themselves and feeling guilty about the food they eat. Do we really have to be reminded that food is essential to life? It is the fuel that runs our bodies and the building material that keeps our muscles and organs functioning and strong. Food should be enjoyed for the life-giving nourishment, both for the body and the soul, that it provides.

The best way to really support your metabolism, is by:

1. Eating regular, balanced meals that include sufficient amounts of all the macronutrients (quality protein, unprocessed carbohydrates and real fats) at each sitting to regulate blood sugar. No under-eating, no skipping meals – food is your metabolic tool. Real foods are those that you could theoretically hunt, pick, gather, milk or fish to obtain. Eat enough food! (see this post for snack ideas)

2.Reducing stress and getting adequate, uninterrupted sleep. Not sleeping and resting enough is a stress that affects your health, and affects your body’s ability to rebuild after day-to-day wear and tear (see nutritional tips for getting a good night’s sleep here).

3.Minimising exposure to toxins (ingested and environmental) including polyunsaturated vegetable oils (sunflower, soybean, canola, corn, etc), tobacco, diet soft drinks, artifical sweeteners, preservatives, gums, flavours and other additives.

4.Light-moderate exercise – over-exercising (particularly with strenuous cardiovascular forms of exercise) and doing zero exercise are both damaging, although over-resting is preferable to over-stressing. Ideally, combine non-stimulating, calming elements for flexibility, such as stretching, with some resistance and weight-bearing training for muscle tone and joint strength and a little stimulating cardiovascular exercise just for fun.

About Kate:

Kate is a certified Clinical Nutritionist and offers one-on-one coaching for clients in Sydney Australia, and internationally via Skype or email. Visit the nutrition services page to find out more about private coaching, and be sure to subscribe via email and follow the Nutrition by Nature Facebook page for blog updates, articles, nutrition tips, recipes and special offers.

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  • lauren

    I am actually HYSTERICALLY crying over this. This is my life right now. I have recently been very, very sick and have gained a LOT of weight. I have no confidence, never leave the house and only wear baggy clothes. I am KILLING myself at the gym, and surviving on a protein shake for breakfast VERY rarely a tin of tuna for lunch and some boiled eggs with spinach for dinner, yet the scales are NOT budging! I can’t begin to tell you how much this is speaking to me…

    • Hi Lauren, I see many, many clients who need help overcoming metabolic damage caused by undereating and overtraining. It doesn’t have to be a horrific experience, weight loss that is! You sound like many of my female clients, killing themselves with diet and exercise to little avail – or worse, weight gain and failing health.
      You’re young and healthy, and it’s pretty easy to turn things around once you have the right metabolic tools (read: food and plenty of it!) to use to your advantage. If you’d like to have a chat properly via Skype just let me know. kate@nutritionbynature.com.au.
      Kate x
      (Clin. Nutritionist. – Nutritionbynature.com.au)

  • laura

    WOW i LOVE this post gave me alot to think about 🙂

  • laura

    fantastic post really made me think 🙂 xx

  • Josie

    This is exactly what i needed to hear!!
    I drastically changed my diet about 6 months ago by cutting out wheat, gluten, dairy and grains. I limited my portions and started skipping dinner.
    Since then I have been suffering from chronic bloating and constipation. I initially lost a lot of weight and have gained it all back since going back to a semi normal eating pattern, however the bloating and constipation is still around!
    No more of this – clean eating and exercising from now on!!
    Thank you!!

  • Amy

    Hey Jessica, great article! I have a question though: how exactly AM I supposed to lose weight without being unhealthy or ruining my metabolism? They usually say that if you use up 300 more calories than you eat everyday, you can lose 1 pound each week, but how can I do this if I can’t cut my calories too drastically or over-exercise?

  • This is a fantastic post! I have gone through many ups and downs in my eating disorder and though i have recovered, i still face these issues and i think this is where i stand now, so its always assuring to read something like this and to think about how what i am doing to my body. Thank you 🙂


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