human body

WTF Fun Fact 13442 – We Have More Bacterial Cells Than Human

The human body contains more bacterial cells than human cells. Weird, right?

The majority of the cells that constitute “you” are, in fact, not human. They are microscopic organisms that are hitching a ride, making a living off your body. It might sound like science fiction, but this is a confirmed scientific fact. The human body contains ten times more bacterial cells than human cells.

How can we contain more bacterial cells than human cells?

Now, before we allow our imagination to scare us into a frenzy, let’s unpack this a bit.

These bacterial cells, collectively known as the human microbiota, live mostly in harmony with our bodies. We provide them with a suitable habitat, and they return the favor by aiding in bodily functions like digestion and immune response. Our gut houses the vast majority of these organisms.

This raises some provocative questions: With our bodies being made up predominantly of non-human cells, what does that imply about our identity? What actually makes us human?

How are we fully human if we contain so many non-human cells?

Biologically speaking, being human is about more than just the number of cells. Human cells, while fewer in number, are much larger and more complex than bacterial cells. So, in terms of volume and genetic material, we are predominantly human.

But the philosophical implications are still fascinating to consider. We ten to link our human identity to our biological makeup. But the massive presence of non-human cells introduces an intriguing paradox.

Science has often categorized organisms based on their cellular composition. However, this fact might prompt us to reconsider such traditional boundaries. We need to acknowledge the complex symbiosis that constitutes our “self.” We are, in essence, a walking, talking microbiome.

Teamwork makes the dream work

These non-human inhabitants of our body have a far-reaching impact on our health and well-being. There’s a dynamic relationship between our human cells and these bacterial cells. When this relationship is in balance, we thrive. But when it’s out of whack, we may face health issues. This fact has driven researchers to explore the potential of microbiota in shaping future treatments for various diseases.

Yet, as we learn more about our microbial inhabitants, we also uncover deeper layers of what it means to be human. Are we individual entities, or are we, as some philosophers might argue, a “superorganism” made up of numerous symbiotic relationships?

Indeed, we might be more ‘alien’ than we ever imagined, yet this very fact underscores our extraordinary complexity as living beings.

So next time you glance at your reflection, remember: You’re not just looking at ‘you.’ You’re seeing an intricate ecosystem.

— WTF fun facts

Source: “NIH Human Microbiome Project defines normal bacterial makeup of the body” — National Institutes of Health

WTF Fun Fact 13344 – Humans Can’t Feel Wetness

The fact that humans can’t feel wetness seems ridiculous at first. You may have even read that it’s a misconception. But, technically speaking, we do not have the right “gear” to directly sense wetness – even though we all know when something is wet.

But how does that work?

Why humans can’t feel wet

Humans lack dedicated hydroreceptors – the specialized sensory receptors solely responsible for detecting wetness. As a result, wetness is not a distinct sensation for us, but rather an interpretation of multiple sensory inputs.

When a liquid, such as water, comes into contact with the skin, several different types of sensory receptors are activated. These include thermoreceptors, mechanoreceptors, and nociceptors. Thermoreceptors respond to temperature changes and can detect the cooling effect of the liquid on the skin. However, this response alone does not convey the specific quality of wetness.

Mechanoreceptors, responsible for sensing pressure and touch, provide information about the physical presence of the liquid. They detect the pressure exerted by the liquid and signal the brain accordingly. However, the activation of mechanoreceptors alone does not differentiate between wet and dry sensations.

Nociceptors, which detect pain and discomfort, may also play a role in the perception of wetness. If the liquid is extremely hot, cold, or otherwise causes discomfort, nociceptors are activated, contributing to the overall sensation. However, this response is not exclusive to wetness and can be triggered by other stimuli as well.

How we sense “wet”

Due to the absence of dedicated hydroreceptors, the brain must integrate and interpret these various signals to create the perception of wetness. It combines the inputs from thermoreceptors, mechanoreceptors, and nociceptors, along with other contextual cues, to generate the subjective experience of being wet.

While humans can recognize and differentiate wet sensations, it is important to note that wetness itself is not a distinct sensory modality. Rather, it is a perception resulting from the brain’s processing of multiple sensory inputs related to temperature, pressure, and even discomfort.

— WTF fun facts

Source: “Humans Technically Can’t Feel Wetness, And People Are Confused” — IFL Science

WTF Fun Fact 13216 – There’s Enough Iron in the Body to Make a Nail

The average human body contains enough iron to make a 3-inch nail. Well, a healthy body anyway. Some of us probably don’t get enough iron.

Is there really enough iron in the body to make a nail?

Humans require iron for many essential bodily functions. Iron is an essential mineral that helps transport oxygen throughout the body and is found in many foods such as red meat, poultry, fish, and beans. It is also found in food additives and dietary supplements, and is added to infant formula as well.

It’s important to note that iron deficiency is a common problem and can lead to anemia, fatigue, and impaired cognitive functioning. The World Health Organization recommends that people consume 10-20 milligrams of iron per day to maintain optimal health.

The average male body contains approximately 4.5 grams of iron, while the average female body contains approximately 3.5 grams. This means that the total amount of iron found in the human body is enough to make a 3-inch nail. Note: nails generally weigh between 2 to 3 grams.

Of course, no one is going to siphon the iron of your body and smelt it into a nail – hopefully.

What’s the significance of this concept?

Nails are often used as a metaphor for hard work. In that sense, it’s no surprise that the idea of making a 3-inch nail from the iron in the human body is a concept that fascinates people.

Iron can also be used to represent the ability to persevere and overcome difficult challenges. It conjures up images of fortitude and determination, courage, ad the will to succeed. Additionally, iron can also be used as a metaphor for protection. often a symbol of armor or a shield.

The metaphor of making a 3-inch nail from the iron stored in the body also speaks to our strength and resilience of the human body. It emphasizes the importance of how the iron in our bodies is used to help us do hard work.

— WTF fun facts

Source: “There Is Enough of This Metal in the Body To Make a Nail” — Soma Blog