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

Lifestyle, Nutrition Advice

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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Hi Jessica, I believe in synchronicity so when I was guided to you .on FB I was intrigued and inspired. I turned 46 last week and my husband bought me your book. I wanted to thank you for sharing your wisdom in such a beautifully presented way. My  copy is now filled with tabs and post it notes with actual notes throughout. I am dairy intolerant since having my gallbladder removed 15+ years ago, I don't eat meat, very minimal gluten and was told 12 months ago my gut was not digesting my food properly so I wasn't receiving sufficient nutrients and taking supplements would be a waste of time.  My weight fluctuates tending to gain rather than lose but now I believe I have a tool to help me bring my body back into balance that I need for my health and longevity of life - so again thank you. The first few steps to creating a stronger path forward for my health has found its foundation in your beautiful book, The Healthy Life.

With kindest regards Samantha

I'm writing this email because I wanted to tell you how much I love your blog and how you really helped me in my health journey. Thank you for sharing all your advices and experiences.

When I started my studies, I was drinking lots of coffee and I was eaten the wrong foods, and feel bad about it, I wasn't at my best. So I had done some research on the net but at first I didn't found advices that are for me, and then I found your blog. It was exactly what I was looking for, good advices and healthy recipes. Now I'm following your advices on rest more, and snacks between meals and prep the meals and take time for myself to reconnect with my body and let go my anxiety, etc, and I have a more balanced life and have a new relationship with food thanks to you.

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Hey Jessica!
I haven’t yet brought ‘The Healthy Life’, but I do have the clean life and your slim down plan! I would like to thank you so much for the knowledge your share and the message you put across about health and wellness. I’m studying Nutritional Medicine in Melbourne and absolutely love the philosophy that you share with your JSHealth community. The work you’ve done to show people that leading a healthy lifestyle isn’t boring, tasteless, difficult or depriving is amazing and hope to share the message myself one day. You’ve inspired me to start my own blog , to share the message and have taught me so many things about my own health! You should be proud of your achievements! Thank you again

- Jacinta

I searched for help and tips through the Internet and found Jessica Sepel. This is seriously not exaggerated, but she was the reason why I have dared myself to eat again, to have snacks in between, to nourish my body. I could slowly improve my negative thoughts about my body image and my stupid anxiety of gaining weight. Besides, The Cleanest Gut was awesome too! A huge thank you! Especially from my mum. Seriously, without you I wouldn’t be where I am now!


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– Sophie

Cooking in this way truly brought out the foodie in me and has instilled a huge passion for health and wellness! Life throws you hard and frustrating things sometimes but I truly believe that this is where we learn more about ourselves and what our passions in life are! Thank you for inspiring me on my journey to health and wellness!


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Michelle Curtis

My fiancé bought your book and we have cooked some of your meals. Amazing! I love your outlook on a healthy lifestyle and your hints and tips with preparing tasty meals are fantastic. Thanks for reviving us to live a healthier lifestyle and get our bodies wedding ready.