Urea, put simply, is a waste product of any living organism that can be found predominantly in pee/urine.
- As we know from week 4’s “D: Digestive Tract”, proteins (like edamame, fish, Greek yogurt, etc.) are broken down into their smaller forms called “amino acids” (AA). Two key steps are involved in this metabolism breakdown process:
- The nitrogen (yes, the same N from the periodic table of elements) contained in proteins is snipped off.
- These amino acids are even further broken down and converted in the liver into ammonia, CO2, water, and energy.
Ammonia is extremely toxic, so we cannot have it leisurely floating throughout the body! So, the body has evolved to quickly convert most of this ammonia into a much safer form called urea. This process is *creatively* called the “urea cycle”. While urea is a safer form of waste compared to ammonia, it’s still waste - so the body must get rid of it by peein' it out.
Our pee is a lovely combination of water (95%), urea (2%), and the remaining 3% is creatinine, uric acid (0.03%), chloride, sodium, and potassium.
The liver and the kidneys tag team this "urea cycling" cleaning of proteins, where the liver takes care of chewing the amino acids into the ammonia, CO2, water, and energy...while the kidneys filter out any remnants of ammonia and toxic urea to pee it out!
FUN FACT: Smelly Pee?!
Diet can affect both the color and the smell of your pee! Urine color may also be affected by certain foods like beets, berries, and fava beans. As urea goes stale (sits out), the environmental bacteria in the air and on surfaces convert the urea back into ammonia! This ammonia-reconversion is the strong ammonia odor you may detect in bathrooms.
About one in five people detect a distinctive odor in their urine after consuming asparagus; other foods such as onions, garlic, and fish can impart their own aromas! These food-caused odors are harmless.
DON'T HOLD YOUR PEE!
Peeing / urination is complex. Simplified, your kidneys and bladder send messages to your brain once it's half full (~1-2 cups) of pee...the brain then generates your "urge to pee" and triggers the ureter to release the pee (source).
Now, if you're on a road trip with no where to pee, in an interview trying to impress your potential new boss, or at the best part of a movie and absolutely cannot pop out to pee...this creates a problem! Not only are you ignoring your body's natural signals, but you're also allowing the toxic minerals (uric acid, ammonia, etc.) to sit idle in your bladder. This can cause infections (UTI'S) and/or kidney stones!! NO THANK YOU.
FUN FACT: Why do gals get more UTI's than dudes?
The urethra, tubes leaving the bladder is the main mode of transportation for pee in the human body, but it’s also an entrance portal for bacteria to squeeze their way into the urinary tract (source). The urethra in females is shorter than it is in males, making it a more speedy highway for bacteria to enter into urinary tract!
KIDNEY AND LIVER OVERLOAD!
Thanks to our badass liver and kidneys, only small amounts of urea and ammonia are found in our pee. However, if higher amounts are found, this could be a red flag 🚩 and mean damage to the filtration system in the kidneys (source). Symptoms of the disorder include lots of ammonia in pee samples (hyperammonemia), growth retardation, muscle weakness, and larger-than-normal liver size (hepatomegaly) (source).
Since protein contains nitrogen, and ammonia (the bad, toxic, clingy boyfriend) is derived from nitrogen, it is thought that excessive-protein consumption diets might be a potential cause for this sloth-like liver and kidney behavior. This is because the liver and kidney get overwhelmed with trying to weed-out all the ammonia from the hefty amounts of protein in the grub you're eating!
FUN FACT: Protein is omnipresent!
Every cell in the body contains protein in its amino acid form- even skin & hair!
HIGH PROTEIN DIETS
I want to make this clear: high protein diets should NOT be demonized! In fact, the recommendation for muscle tone, maintenance, and performance is to consume 1 gram of protein per 1 kg of body weight. So, if you weigh 165 lbs., that's 75 kgs. It would be recommended that you consume 75 grams of protein per day!
Protein is what I and most trainers recommend our clients consume to maintain muscle due to its role in muscle growth & recovery...as well as tissue & ligament healing.