You: Staying Young: Make Your RealAge Younger and Live Up to 35% Longer. Michael Roizen F.

energy to prayer. It’s these energy fields – your life force, your chi, your intangible aura – that we believe will be the next great frontier of medicine. Your nerve cells, in fact, touch stem cells in the liver, which might explain a more direct connection between the mind and self-healing. Many people believe that it’s through these energy fields that prayer may work for them – and, thus, how the mind-body connection works. And it may go on to explain why other things work, like the ageing process.

      In addition to giving you the chemical tools to beat the dickens out of your stressors, stress hormones also work throughout various regions of the brain to influence everything from mood and fear to memory and appetite. And they also interact with hormonal systems that control reproduction, metabolism and immunity. See where this is going? The HPA axis is like a curious two-year-old, touching everything in its path. That’s OK in short spurts, but not when you overfill your hormonal systems. That’s why stress is so highly correlated with bad health. Specifically, this is what happens when you let the hormones in the HPA axis run crazy:

      

An overactive HPA axis can mean that your body is unable to turn off your stress response. So? That can lead to anxiety and depression, which are further manifested through such things as low sex drive and high blood pressure – both associated with ageing.

      

When the HPA axis is flooded, we also experience other potentially fatal health problems, like elevated lousy LDL cholesterol or triglycerides combined with reduced healthy HDL cholesterol. Part of this risk comes from a stress-related surge in chemicals called cannabinoids (discussed here), which cause us to eat and can eventually lead to such conditions as diabetes and the biggie, literally, obesity.

      

Cortisol prevents the release of chemicals that strengthen your immune system (see Figure 3.2). That’s why you tend to get sick when you’re stressed out. Too much cortisol essentially suppresses your immune system and decreases your ability to fight infection. Stress also makes you more susceptible to diseases that you rely on your immune system to hold at bay or eradicate, like cancer. Men have a pretty quick rebound from the cortisol release during stress, but women often sense a lingering impact of the hormone, which is why men are so chipper the day after a lover’s spat that they have already forgotten it, while women retain perfect recall of the event, together with the emotional undertones.

      

CRH prevents the release of a hormone that controls all the hormones responsible for reproduction and sexual behaviour, including those that control ovulation and sperm release. Indeed, reducing stress is one of the tactics used by couples with fertility issues. They’re relaxing not just for some mumbo-jumbo reason but to try to make their bodies better equipped hormonally for conception. Makes evolutionary sense, right? Why would you want to produce babies in the middle of a drought or when fighting off hairy four-legged neighbours?

      

If the HPA axis is activated for too long, it hinders the release of growth hormone. As you’ll learn in future chapters, you need your growth hormone to help combat some ageing-related diseases and conditions and to build lean muscle mass.

      

If you keep the axis activated for too long, it can develop an exhausted response – and that produces a wiped-out feeling when stress does come.

Figure 3.1 Stress Test The hypothalamic-pituitary-adrenal (HPA) axis connects the nervous system and the stress hormones. It all starts with the hypothalamus releasing a stress hormone that influences your pituitary gland to release another hormone into your bloodstream that stimulates the adrenal glands and your autopilot nervous system. The result: your blood pressure goes sky high.

Figure 3.2 Captain of Stress Stress hormones whip one another into a frenzy when you have to fight or flee. As captains of the stress team, cortisol soothes your response (by turning off your immune system), and epinephrine gets your blood moving (sometimes too quickly). You survive to live another day, but at a price.

      So what role does our Major Ager of stem cell slowdown play in all of this? Well, the stem cells’ regenerative properties are crucial here because of the damage that our environment and the resultant stress can do. Stress is all about adapting to the challenges of life. It is not the strongest or the fastest who wins the game of life, but the most adaptable. When stress hormones damage tissues, cells and organs in the ways we talked about above, stem cells replace damaged cells and make the repairs. It’s one of the reasons why we can’t constantly be mentally revved; we need to idle our brains to allow the stem cells to do their job and replenish those cells and tissues that have been battered by bosses, bullies or brats. So when a toxic food has shrivelled our liver, or having a baby has reduced our heart function, or we have damaged an artery by overreacting to a sloppy coiffeur, stem cells come to the rescue to rebuild us as good as we were before. To boot, stress shortens those telomeres and turns down telomerase, so that the fastest-producing cells – stem cells – have the most difficulty keeping up.

      Even five years ago, we didn’t know this stem cell replenishment was true for most organs, but now we know that every organ seems to recruit backup stem cells from the bone marrow to resuscitate itself. These emergency relief worker cells lay the groundwork for re-creating our organs.

      Stress has a cascading effect on many aspects of our health. It increases the risk of arterial ageing, it damages our immune system, and it also makes us prime candidates for life-altering (or life-ending) accidents – many accident victims admit to having been stressed and angry before the mishap – not to mention affecting our mental health. Stress also releases steroids, which, when given in higher prescription doses, are a legally defensible reason for a rage response. Stress isn’t just something you write off as a need for spa treatments; it’s a major biological driver of ageing.

      Now, your response to stress is somewhat hereditary. We all have differences in our genes that control the HPA axis, meaning that some of us never have a strong response to a threat, while others have a full-fledged response to even a minor threat. (Sound like anyone you know?) But that hereditary predisposition can be altered at any time by extreme stresses. With major stresses early in life, your response becomes stronger, making you better able to handle future stresses. We see an example of this with our response to something called heat shock. When exposed to extreme heat, all animals, including humans, learn to adapt to the temperature so they can respond to it the next time they encounter it. It’s the biological basis of the mantra that what doesn’t kill us does indeed make us stronger. There are plenty of other techniques that can help minimize the internal damage caused by the pressures from the external world.

Your Belly: Stress Barometer

      When our ancestors faced periods of famine, they stored fat in their bellies with an organ called the omentum. We do the same thing: when we face chronic stress, we eat more food than we need, and we store it in our omentum for quick access to energy. The steroids released by the HPA axis are also sucked up by the omentum and help grow it as big as the muscles on a weight lifter who is dabbling in similar chemicals. That process proves to be damaging because the toxins from our omentum fat are pumped directly into surrounding organs. But it also offers a tangible way to gauge our stress levels: the bigger our bellies, the bigger our burden.

       YOU Tool: Anger Management

      It’s no secret that anger doesn’t help