Cut Your Kidney In Half

An analogy for weight and fat loss, and an attempt to describe part of the difficulty in doing either.

Broadly speaking, ‘Fast Facts About Biology’ can hardly be beat. Male sea horses become ‘pregnant’, neutrinos (even the name is great!), that Weddell’s seals can hunt for up to an hour beneath the surface of artic ice… I find facts about human biology even more interesting; your foot is the size of your forearm, your bone is as strong as granite. Your skin is an organ (that you knew). Fat is an organ (that you didn’t).

While carving out the research plan for Fat Planet, I stumbled upon this fascinating point: Human Fat is an organ. It communicates with the body and your brain. It secretes hormones. By understanding the way fat interacts with your body, we may gain a greater appreciation for the incredibly daunting task of fat ‘loss’.

We have come to accept fat as an empty sink of energy. Representing the excessive consumption of calories, fat on humans is assumed to symbolize two things: for the most forgiving audiences, a somewhat beguiling tendency towards overconsumption.

For the most ignorant ones, greed. However, if more people knew that fat was in fact an organ, would our understanding of obesity change? If someone had an extra large heart or kidney, would you accuse her of laziness? Or worse: stupidity? With growing appreciation for the Fat Organ issue, it’s my hope that more people will take a more humane approach to obesity. Here are a few more Fat Facts…

Fat Facts

Human babies are the fattest of the animal kingdom. Weddell’s seals can compete, but considering their neighbourhood- freezing cold arctic waters and ice caps- it’s a small wonder they need a built-in set of insulation. Their extra fat makes a lot of evolutionary sense.

Although I’m far from having expert knowledge of fat physiology, this I can promise: human fat does way more for the human body than to simply insulate it. If our brains are undeniably more complex than a Weddell’s Seal (or anything in the mammalian kingdom), couldn’t it mean that our fat is, too?

A big surprise in research is that human fat may not (in fact) be such a great insulator. Instead, fat may be more useful for secreting appetite and also sex-related hormones.

At the forefront of appetite control we have leptin and ghrelin; these hormones essentially control our feelings of hunger and satiety. Leptin makes us feel full and ghrelin makes us feel hungry. It might be surprising to know that leptin levels are actually higher in obese children and adults. Paradoxical, but true: the more fat you have, the more leptin is in your blood. Scientists believe the brains’ resistance to leptin is a core culprit in obesity. Beyond leptin and ghrelin, fat also secretes sex hormones like estrogen, and is responsible for the production of over 80 different proteins. Thus, fat is not simply dormant storage for energy. Too much of it may contribute to chemical messages that tell your body it’s under threat: this may be a key factor in having a heart attack, not the idea of having too much fat mass.

Suffice it to say, fat is far more complex than we had previously thought.

Give Me Some Skin… or Half Your Kidney

In addition to hormones like leptin, ghrelin, adiponectin, and estrogen, fat also behaves differently throughout the body. For whatever reason, abdominal fat is associated with the chronic inflammation that leads to heart disease.

Looking at fat distribution could provide an important clue to an individual’s actual health: simply comparing weight with height may be too vague (as is customary with the use of BMI). Moreover, this won’t describe the health of the fat organ. My hunch, is that if your fat organ has grown out of shape, and is very close to the majority of your organs, you may be at risk for a host of illnesses- from Cardiovascular Disease to a variety of forms of cancer.

So, let’s put all of this information into the context of weight loss. Do you see how ‘just’ losing 15% of an organ might be a tall order? Try it. ‘Just’ give me 15% of your skin. Just give me 25% of your kidney.’ I’ll have half of your spleen, thanks.

That’s insane!

Weight loss is infinitely more complex than ‘losing fat’ (or burning it, or cutting it (ouch!)). In time, we may have more clues about the biological perhaps even psychological purpose fat serves humans. For Weddell’s seal it is patently obvious: fat protects the organism from an exceedingly taxing environment. However, our current environment doesn’t pose as much of a threat. We have central heating. Air conditioning. Cars. And cell phones.

Now, a final consideration. Perhaps for humans fat is in fact similar to the Weddell’s seal: providing protection of some sort. A bi-product of a hyper stressful environment, achieved by a drastic changes in the food, social, and digital environments. Broadly speaking our food and digital landscapes have developed extremely quickly within the last thirty years. These two great leaps may have caused a lot of stress to our relatively primitive brains; in terms of the cognitive cost of rational decisions in an environment of dizzying abundance.

Is this as stressful as subzero arctic waters? It might be something to think about.

The future will depend on effective ways to manage, educate, and help people to understand obesity. In light of our utter ignorance about the Fat Organ (let alone the complexity of behavioural change required for weight loss), I believe obesity will continue to be the Disease of the 21st Century.

We don’t know enough about fat/brain communication. Most people don’t know, not really anyway, that Fat is an organ. By understanding basic fat biology, we may gain a greater insight into the human species, its environment, and finally: how to make meaningful improvements. Hopefully, we’ll be able to string some of our knowledge into ‘Fast Facts About Obesity’. For the mean time, a lot of research is still required.