“I’m useless ‘til I’ve had my morning coffee.” How often have you heard this statement from a coworker, a friend, or even yourself? It’s almost a cliché in our culture that to get ourselves going in the morning, we need a caffeine jolt first thing — many of my patients reach for coffee, tea, or cola before they’ve even gotten dressed or had breakfast.

And you know, there’s nothing wrong with that — in moderation. But for many women, caffeine masks an adrenal imbalance that may be preventing them from restful sleep. If a woman says she simply can’t function in the morning without caffeine — or that she needs “booster cups” later in the day — that’s when she might start thinking there could be an issue with her adrenals.

Caffeine itself isn’t the sole cause of adrenal fatigue, but many of the changes our bodies undergo when we use a lot of caffeine can strain our adrenals. If we substitute a cup of coffee for sleep or for a nutritious meal, it can undermine our adrenal health. So let’s take a closer look at how caffeine affects our bodies — our adrenal glands, in particular.

Caffeine stimulates the stress response

Caffeine is a psychoactive stimulant, which means it increases the rate at which neurons in the brain fire and stimulates both the central and sympathetic nervous systems. This stimulation is similar to our natural “fight or flight” reaction to stress. Both originate along the HPA axis: with just 100–200 mg of caffeine (less than one short cup of Starbucks drip coffee), your Hypothalamus, Pituitary, and Adrenals begin pumping out stress hormones — epinephrine (aka adrenaline), norepinephrine, and cortisol.

These stress hormones are needed for our bodies’ innate response to a real or perceived threat, sending the message: Think fast! Act fast! That’s why, after that cup of coffee your pupils dilate, your heart beats faster, your blood vessels dilate, your breathing intensifies, your muscles contract, and your liver releases sugar and free fatty acids into the blood for instant energy. You may also feel more anxious and worried, with no more cause for these feelings than the shot of caffeine you just drank. You are literally poised and ready to outrace and outwit any danger — but most of the time you’re sitting at your desk or behind the wheel of your car.

That’s great for productivity and alert driving. Your adrenals’ “mission critical” is to ensure survival. But the secondary function of our adrenal glands is to provide for hormonal balance across the life span — and this function is particularly important as we get older.

Caffeine, adrenals, hormones, and insulin — a complex relationship

Caffeine isn’t likely to do most women much harm if it’s just a cup or two a day. Of course, some women are highly sensitive to caffeine, but that’s rare. For many more women, caffeine becomes a problem when it’s used too often or at the wrong time of day (in the evening, for instance). That’s because caffeine disrupts the regular rhythm of cortisol. In effect, it distances you from your natural energy cycles, tricking your body into a state of emergency or high cortisol — which ultimately makes you feel more tired. If you use caffeine to offset fatigue, your solution may actually be part of the problem — especially if you become too wired to rest when the time comes, and start reaching for more caffeine.

But the adrenal glands don’t just produce stress hormones — they also help to maintain levels of sex hormones as a woman transitions into menopause and her ovarian function tapers off. They just can’t do that when they’re constantly under siege — whether from real stress in your daily life, or from a turbo-charged caffeine hit every few hours, day after day. So indirectly, caffeine may be affecting your hormonal balance.

Another piece of the puzzle is insulin resistance. Normally when you’re under stress, an increase in cortisol levels will prompt more glucose to be released into your bloodstream. Then your pancreas increases its insulin output, to usher all that extra glucose into your cells, where they can fuel your “superhuman” response to the “threat.” But in women whose cells are already insulin resistant, studies show that caffeine exaggerates their glucose and insulin responses. That’s one reason why you may experience sudden energy dips in mid afternoon if you’re caffeine-dependent in the morning — not only has the caffeine jolt worn off, but it has affected your insulin activity such that your blood sugar can become low in the mid afternoon, making you feel fuzzy-headed and fatigued. So you reach for more caffeine to clear your head, and sometimes more carbs as well, which just makes the cycle repeat all over again — and simultaneously worsens the insulin resistance (particularly if your caffeine is paired with sugar).

A lot of factors determine caffeine’s effect on insulin sensitivity. For example, it varies significantly between men and women; what condition the body’s in; whether caffeine is taken when fasting or with meals; and whether it’s paired with carbohydrates — particularly when taken with sugar. What’s more, tea does not appear to have the same insulin-deregulating effects as coffee. In fact, research suggests that tea does the opposite — it actually helps reduce blood glucose — because of its polyphenol content, rather than any action of caffeine. But even though we’re still connecting the dots on all this, the data clearly cast caffeine as a highly active metabolic agent that impacts both insulin resistance and adrenal stress imbalance. The two issues compound one another, and it’s very common for women to have both. Which comes first is like the chicken-or-egg question --, so for optimal healing, you should address them both at the same time.

Finding healthy balance between caffeine and adrenal health

We realize that caffeine is not an easy drug to quit for some women. Caffeine is an addictive substance, both physiologically and psychologically, so stopping “cold-turkey” may cause you so much stress and discomfort that its absence does you more harm than good. (After all, when healing the adrenals, the goal is to minimize stressors!) So when you’re ready for a caffeine detox, remember that it’s not something that needs to happen all at once. If it takes you a while to cut back, that’s okay. Adrenal healing doesn’t happen overnight, and we wouldn’t want you to expect it to!

The message here is not that you must live the rest of your life without caffeine — rather, you may want to consider a caffeine holiday to help your adrenals heal. But you’ll need to look at your eating habits and stress patterns, too — which will actually be easier if you eliminate the “noise” that caffeine creates between you and your body’s natural rhythms. There are great herbs for energy that can help boost your adrenals too. Once the adrenals recover, you’ll be in a much better place to create a healthier relationship with caffeine.


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