Early mornings are common culture among the strength training community. Sessions begin at 5:30am with an alarm clock that rings well before this time. Coffee has been a staple of our being (for most), and provides a “pick me up” for the early morning commute, long days on the floor and the hours of continuous education. Truth is, for the last ten years I’ve drunk enough coffee to support several Tim Horton’s franchises, and ingested enough caffeine to make the FDA reconsider what “normal consumption” truly is. The result is that I grew more and more mentally tired. Mid day exhaustion, yawning on dinner dates, and a bedtime that resembled that of a middle school student. It wasn’t until recently when I started to research the effects of caffeine consumption and adrenal fatigue that I realized the beverage I craved the most, may be the plight of my condition.
Today Americans are the largest consumers of coffee in the world, drinking over 420 million cups/day. In conjunction to this, over 100 million Americans drink more than three cups each day. This begs the question, what is considered a serving? How much is too much? Can excess caffeine cause problems?
Serving Size?
Because caffeine is not considered a nutrient, the FDA does not require manufactures to list the amount of caffeine in their products. The FDA has stated that for healthy adults, caffeine intake of up to 400 mg per day is not associated with negative health impacts.(1) The question many of us have is, what is 400mg? Most studies claim that a standard cup of coffee is 6oz, roughly the amount held in a teacup. The caffeine content in a standard 6oz cup can range from approximately 37-148 mg respectively.
I know from experience, that before I got to the gym in the morning I was already over my 400mg limit. Think of how many people tax this limit each and every day without even knowing. In the midst of our caffeine frenzies we order super mugs, XL coffees, espressos, lattes and pay no attention to serving size. If you drink three coffees in the morning, a large coffee (20z, or 3.5 servings), and another mid day, consumption would look like this:
3-6oz cup: 111-296mg
1 Large cup = 129.5-518mg
1-6oz cup: 37-148 mg
Total Caffeine: 388-962mg
On the low end one is already reaching threshold consumption and that’s with 6oz servings. How many people truly drink out of a 6oz cup? I would suggest very few. In addition, biochemical individuality means that everyone will respond differently to these doses of caffeine. Low-end doses may be threshold for others.
The Affects of Overconsumption
Coffee does not give us energy: coffee = stress!
The adrenals are the glands of stress. They are no larger than a walnut and sit on top of the kidneys just above the 12th rib. Under normal functioning conditions the adrenals secrete precise and balanced amounts of hormones (epinephrine and cortisol) that keep our bodies functioning in the ever-changing environment of stress and recovery. However, when chronic stress outpaces the ability to recover, adrenal fatigue may ensue. Coffee stresses the adrenals and shifts the body into a “fight or flight” response. Think of overdrawing your bank account and leaving a negative balance. When the adrenals are fatigued the account is compromised. Here’s how it works:
The HPA (Hypothalamic Pituitary Adrenal Axis) functions as a negative feedback loop.
- Thermostat=Hypothalamus
- Switch=Pituitary
- Furnace=Adrenals
- Room=Body
When caffeine alters the HPA axis, the negative feedback system is altered. “A single 250-milligram dose of caffeine (the equivalent of about 2 ½ six ounce cups of coffee) has been shown to increase levels of stress hormone epinephrine by more than 200%.” (2) Chronic overconsumption may lead to problems!
- Hypothalamus (thermostat) is exhausted. Coffee blocks adenosine receptors in the brain. Adenosine is responsible for dampening, or slowing down neuron firing rates. If the neurons cannot relax, the brain is in a state of constant panic. This leads to mental fatigue and exhaustion.
- Pituitary (Switch) stops producing ATCH. Coffee stimulates the stress response, which prompts the pituitary gland to release ATCH. Chronic overconsumption of caffeine alters the function of the pituitary. It can no longer perform its jobs efficiently or effectively.
- Adrenals (furnace) stop/reduce cortisol production. Caffeine initially stimulates the adrenals to increase cortisol and epinephrine production. Abuse of caffeine depletes the adrenals and blunts receptor affinity leading to adrenal fatigue and low blood sugar levels.
- The body’s (Room) homeostasis is altered. Low blood sugar, mental exhaustion, calcium depletion, increased levels of LDL cholesterol, and reduced iron absorption have all been documented and experienced during periods of high caffeine use.
Moderation is key. Whether or not you’re willing to kick the caffeine habit is a personal choice. Keep in mind, just like good strength training, rest and regeneration is just as important as exercise. Without rest gains cannot be experienced. The adrenals are no different. Constant consumption of caffeine stimulates and eventually over trains and depletes this system. The very thing you reach for to give you energy, gives you nothing but fatigue.
References:
1) Nawrot, P., et al., 2003, Effects of caffeine on human health. Food Additives and Contaminants, 20(1), 1-30.
2) Cherniske, S., Caffeine Blues, Grande Central Publishing, 1998.