Hands up who knew that we have a hormone nicknamed by some the ‘fountain of youth’ inside our bodies, that under certain conditions, is released freely into the blood. No, me neither until very recently.
This hormone called osteocalcin is critically involved in maintaining bone density and strength but has also shown to be crucial for keeping our muscles strong and fit, increasing exercise capacity, keeping the brain alert and cognitive functions high, helping to regulate blood sugar, fat and general metabolism. It is an important hormone in the prevention and treatment of diabetes, is intricately involved in our response to stresses, helps to regulate male fertility and reproductive health and is important in slowing down the age related decline of both our physical and mental capacity.
Osteocalcin, as the ‘osteo’ part of its name suggests, is produced by osteoblasts, a type of cell present in the bones. Maintaining strong healthy bones is a dynamic interplay mainly between 2 types of bone cells – osteoblasts (bone builders) which lay down new bone material and osteoclasts, which break down older bone material to make way for the new.
Osteocalcin production rises significantly in response to stress.
In humans (and all mammals) the stress response or ‘fight or flight’ as it is known causes adrenaline to be released from the adrenal glands. This produces physiological effects in the body that include a raised heart rate, increased breathing rate, increased blood flow to muscles and a rapid release of glucose to be used as fuel. It is now known that this adrenaline release is not possible without the presence of the hormone osteocalcin. Almost immediately after we perceive a threat or stressful situation, the brain instructs the bones to flood the bloodstream with osteocalcin which then initiates adrenaline release. Researchers have demonstrated that if a person or mammal with no adrenal glands (and therefore no adrenaline) is exposed to stressor danger, a measurable stress response form the body still occurs. However, if a person or mammal has no skeleton, no bones, (don’t ask!) the standard stress response (increased heart rate etc) is absent. If osteocalcin is then injected into the boneless creature, this will induce a marked stress response. Conversely, when mice where genetically modified to produce no osteocalcin, they had no physiological response to stress at all.
So how is osteocalcin the ‘fountain of youth’ hormone?
The bones of our skeleton are not just useful as a means of escaping danger, the osteocalcin released from them has an effect on the brain, the pancreas, metabolism (how the body uses its fuel), muscles, the kidneys, male fertility and more.
Osteocalcin is also released when we exercise where it mobilises fat stores, raises blood sugar and enhances its uptake into muscle cells and helps the muscle fibers metabolise both glucose and fatty acids more effectively. Its presence means we can exercise more efficiently for longer meaning our bones have a direct impact on muscle performance, both strength and endurance. However, osteocalcin production and resting blood levels begin to decline with age, around the age of 30 in women and around 50 in men. Interestingly, researchers found that when older mice were given osteocalcin their exercise performance matched that of much younger mice.
Exercise endurance and muscle strength are not the only benefits of oseteocalcin. It also has a positive effect on the brain and cognitive abilities such as learning, memory, anxiety, depression and prenatal brain development. Experiments determined that it crosses the blood-brain barrier and has receptors throughout the brain where its influences promote the formation of new nerve cells, increases the production of neurotransmitters like serotonin, dopamine and catecholamine (important factors in overall mood and mental health) and enhance memory and learning. Mice that were engineered to produce no osteocalcin showed signs of anxiety, depression and had less memory and learning skills than normal mice.
Studies carried out on women in their 70’s determined that those with higher osteocalcin levels had better memories, learning abilities and ability to execute their learning than those with much lower levels. Experimental treatment with osteocalcin on those with low levels of the hormone found their overall above abilities increase.
The impact of osteocalcin on the developing baby is crucially important. Undernourished mothers with poor bone health and therefore lower levels of the hormone produce children that are more likely to develop metabolic diseases, psychiatric disorders and cognitive impairment.
Osteocalcin is directly involved in strengthening bones and preventing fractures (unless the impact on the bone is too great). Studies suggest it may be vital in preventing and treating osteoporosis.
It also increases testosterone production in men and leads to better sperm health, increasing fertility and general drive. It is known that the growth and integrity of the bones in both young male and females is influenced by steroidal sex hormones but it appears that reproductive health and fertility is also influenced by the bones.
It lowers the risk of diabetes by regulating and controlling blood sugar levels, increasing insulin production and improving pancreatic function. It can also help prevent obesity by increasing energy expenditure.
How to ensure a good supply of osteocalcin
The hormone, once released from the bones, has a relatively short life cycle of between 20 minutes to an hour. We know that bone density generally declines with age, along with memory, new learning capacity, muscle strength and endurance. Research suggests that osteocalcin levels fall too. Here are some things that we can do to help maintain and/or increase levels.
Eat an apple every day. Asian studies have found that a substance in apple peel increases both bone formation and osteocalcin levels.
Eat vitamin K rich foods. Osteocalcin needs vitamin K to be fully functioning in all its roles so eat plenty of leafy greens such as kale, sprouting broccoli, Brussels sprouts, cabbage, pickled cucumbers and sauerkraut, asparagus, kiwi fruit, okra, green beans and dark green lettuce, in fact any leafy green like watercress, spinach and culinary herbs like parsley and coriander.
Cold pressed olive oil and olives have been shown to directly increase osteocalcin levels, especially when coupled with a Mediterranean style diet rich in wholefoods like fruit, vegetables and nuts.
Go for a brisk 20 minute walk each day. Consistent (daily) exercise increases osteocalcin levels.
The seeds of milk thistle and the horny goat weed plant have both demonstrated the ability to increase osteocalcin levels.
Vitamin D is also linked to activation and availability of osteocalcin so a 15 minute sunbathe (without sunscreen) daily if possible is a good natural source.
Other useful nutrients linked to higher osteocalcin levels include manganese, iron, omega 3 fatty acids and ellagic acid..
Think carefully about taking biphosphates. Biphosphates are commonly prescribed for osteoporosis or low bone density. They reduce or inhibit the bone modeling process (absorbing old bone and making new) with the intention of reducing bone loss and fracture risk etc. However, by inhibiting the bone modeling process, osteocalcin production is reduced significantly.
Avoid steroid medications where possible, these reduce osteocalcin levels.
Limit where possible your exposure to xeno-oestrogens – these are oestrogens that come from the environment. Oestrogen is known to suppress osteocalcin.
Stop smoking as it lowers osteocalcin levels.