Is it really as simple as "calories in, calories out"?
For someone who has struggled long and hard with weight loss, hearing the old adage of "calories in, calories out" can be infuriating.
By far and most commonly, it is women on the receiving end of that statement, some of whom are actually eating far less calories than they ever should, and yet they're still not losing weight. So what gives?
While at the most basic, molecular level, it is true that an excess of energy must be used in order to see a reduction in fat mass, there is definitely nothing linear about the process -- the body is a complex system!
It is important that this complexity of weight loss is understood and acknowledged more broadly because the adoption of this reductionist and simplistic mindset of "calories in, calories out", fails to take into account the individual and all the hormonal elements that drive not only appetite and metabolism, but also how (and where) fat is created or broken down.
Particularly for women, this disregard for their struggle is evident. I've had women tell me even their doctors have dismissed their struggle, telling them to exercise more and eat less, despite them explaining they have and it's not been working!
The struggle is real for many and it needs validation and investigation to try to figure out why. While men tend to fair better with the basic "exercise more, eat less" model, women are not small men, and their hormone profiles are far more complex.
Let me highlight some of the ways women can have unique challenges when it comes to weight:
Monthly alterations in hormone levels, influencing water retention, insulin sensitivity changes, energy levels, food cravings
Significant drop in hormones at menopause, contributing to reduced energy, abdominal fat storage, increased appetite, lower quality sleep
Body shape changes related to pregnancy including wider hips
Much higher likelihood of having hypothyroidism which drops metabolism and reduces energy (many of whom are "subclinical" or are poorly managed, even when taking medication)
1 in 10 women suffer from polycystic ovarian syndrome (PCOS) which alters hormones and involves insulin resistance
Women tend to be more stressed than men, often managing both work and family which impacts energy, free time to exercise, elevates cortisol and can compromise sleep
Birth control pills are associated with weight gain and difficult weight loss
Women in general have higher body fat than men and less muscle mass which leads to a lower resting metabolic rate
Men can certainly struggle as well though, and it's no surprise why when we consider all these other factors that can influence weight:
Insulin resistance (you don't have to be diabetic -- this typically happens 10-15 yrs before someone becomes diabetic)
Estrogen dominance (in men and women)
Low testosterone
Gut dysbiosis and inflammation
Food sensitivities
Elevated stress and cortisol
Compromised sleep
Chronic systemic inflammation
A diet high in fructose, even if calories are low (ie: high fructose corn syrup found in pop, sweets and processed foods)
Certain medications (ie: insulin, prednisone/cortisone, antidepressants, hormone therapy, beta blockers, asthma inhalers, antihistamines )
Subconscious factors that promote self-sabotage, unhealthy habit adoption, limiting beliefs, poor stress management strategies, etc (this is why I incorporated hypnotherapy into my practice)
And on top of all this, researchers have identified genetics, ethnicity, overactive endocannabinoids in fat tissue and obesogens (environmental toxins that promote obesity) as contributing factors to weight as well.
As you can see, there is a complex interplay of factors that can make weight loss very challenging for some people. Researchers are not entirely clear why some medications cause weight gain and they are just beginning to uncover all the ways environmental toxins are influencing fat storage.
This is why personalized healthcare is so important. Each individual has their own unique biochemical and personal profile that determines not only the ease with which they can lose weight, but their health on the whole.
Weight loss, just like many other aspects of health, cannot be a "one-size-fits-all" approach, and the focus and priority should always be on optimizing the health of the body.
So the next time you hear someone say "it's just calories in, calories out", be sure to give them the facts (and maybe direct them to this article).
References
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