As my friends and I clipped our cleats into our spin bikes last Sunday morning, I warned them I was feeling worse for wear. "Big night last night?" they asked. Far from it. I'd had a few glasses of wine with dinner – so why did I feel like I used to after countless cocktails and shots?
My alcohol intolerance is particularly irritating because it's inconsistent. Sometimes I can drink way more than a measly two glasses (don't tell my doctor), and it barely touches the sides – "There's nothing in a bottle!" my friends and I frequently proclaim, ordering a second and feeling right as rain the next day.
So, what is it that makes my constitution go up and down like a rollercoaster?
I promise it's not perimenopause
I've spoken to many midlife women about how their alcohol tolerance tanks in perimenopause and beyond – Donna Francis, who turned sober in her 40s after alcohol no longer agreed with her, writes beautifully on the topic. In short, in midlife, your alcohol tolerance tapers due to the hormone shifts in your body.
"When your oestrogen and progesterone levels are fluctuating, it triggers a change in your gut microbiome which makes your gut slow down, meaning you're not able to metabolise alcohol as effectively," says Dr. Taz Bhatia, author of The Hormone Shift. "That is why a lot of women can't tolerate drinking like they did when they were younger."
But at 36, I'm fairly certain it's not perimenopause wreaking havoc with my ability to drink alcohol, so what gives?
Why does my alcohol tolerance constantly change?
I asked nutritionist and hormone expert Hannah Alderson for her take on the matter during a live Q&A here at Best Quality Designer Handbag , and she explained that while it's not perimenopause, hormones are to blame for why my ability to drink is always shifting.
As Dr. Bhatia explained, Hannah notes that oestrogen and progesterone influence how alcohol is metabolised and how it affects the brain – but she links it to our monthly cycle rather than midlife.
Periods and alcohol
Hannah explains that at different stages in our period, the landscape changes hormonally, which means alterations in metabolism, body temperature, blood sugar regulation and even our stress resistance – so it's probably safe to say that our tolerance to alcohol will shift too.
Alcohol in the luteal phase: Increased sensitivity
"In the luteal phase (before a period), higher progesterone can make you more sensitive to alcohol's effects (disrupted sleep, worsened anxiety and stronger hangover symptoms) as progesterone can slow liver enzyme activity, delaying alcohol metabolism," Hannah begins. This continues where our period arrives, too – the menstrual phase, which can make our alcohol tolerance feel lower.
Drinking in the follicular phase: Higher tolerance
During the follicular phase, Hannah says it's likely that we may feel we tolerate alcohol 'best'. "This is because when our oestrogen gradually rises, energy tends to improve and insulin sensitivity is generally more optimal.
"Many women report feeling more resilient physically and mentally during this stage. That said, alcohol still impacts sleep, liver detoxification and blood sugar, even if symptoms feel less noticeable," Hannah warns.
Alcohol when we're ovulating: Loss of control
As for ovulation, oestrogen is at its highest at this stage may increase alcohol absorption and make alcohol feel more potent.
"When it comes to ovulation, research shows that higher levels of oestrogen can increase brain sensitivity to alcohol's disinhibiting effects. This means women may feel more intoxicated or lose control of their drinking sooner during this phase."
Mixed messaging
"Interestingly, like many hormone-related topics, the research in this area is still pretty mixed, which is important to acknowledge," Hannah laments.
"Some studies suggest women may drink more or crave alcohol more in the luteal phase, potentially linked to shifts in progesterone, mood and the brain’s reward pathways, whilst other studies show very little difference across the cycle."
Hannah also cautions that it's important to note that alcohol itself can impact and temporarily influence hormone levels. "Alcohol may increase circulating oestrogen levels, particularly after heavier drinking episodes."
Changing my ways
I already track my period on Natural Cycles, and I know some people who use this data to plan the workouts they're going to do (Hannah says this isn't necessary, noting: "I would rather you got some exercise in, rather than worrying if the exercise you want to do 'fits in' with your cycle – this can end up being a barrier,") so do I now need to monitor my cycle to decide if I'm going to drink alcohol?
Realistically, probably not. I can't see myself opening Natural Cycles before I ask for the wine list or turn down drinks with friends because my cycle says alcohol will be an issue that day, but I am happy to know that I'm not imagining my low tolerance at certain points in the month.
