Coffee and weight loss
You may (or may not) be aware that genes play a part in determining how rapidly your body will process caffeine. The gene CYP1A2 is responsible for the metabolism of caffeine and in some of us it will be rapid whereas for others it'll be slow.
That's partly why some folks can drink 3-4 cups a day and even have them before bedtime whereas others need to sip the last drop before lunchtime if they want to get any sleep.
But what's that got to do with weight and weight loss?
A lot actually.
Coffee itself won't make you gain weight. It contains zero calories and if taken without added milk, can be consumed all day with no effect on your waistline.
Where coffee and weight gets more complex is due to how our bodies digest the caffeine, how many cups we drink and what we have with it.
Skinny flat white with two sugars?
Is it the caffeine that makes you fat?
Caffeine has an affect on your metabolism and is known to give it a boost. But over time, the effect of caffeine on our system can cause a negative effect on our hormones due to the way caffeine increases the production of adrenalin.
Which we already produce enough of. Hello, stress?
As with everything, some people will experience a positive effect from drinking coffee - faster metabolism, boost in mental energy, while others will suffer.
Dr Libby Weaver, internationally acclaimed biochemist and expert on women's health, says caffeine creates hormonal changes that can produce weight gain. According to Weaver, caffeine affects the balance of your nervous system which can lead to the body to store fat.
In her book Accidentally Overwight, one of Weaver's clients went from drinking one black coffee a day to four, and gained 3kg. When Weaver persuaded her to reduce her coffee intake back to one, her client lost 4kg!
That was without any other dietary changes.
Flat white, latte or cappuccino?
According to the 2018 Square Australian Coffee Report, Flat White is the most popular coffee choice in WA, NT, ACT and QLD, with latte taking the crown in VIC, SA and TAS. NSW prefer theirs with a sprinkle of chocolate a la cappuccino.
That's a lot of milk.
And milk contains fat and calories, which is another reason your morning coffee could be increasing your waistline.
According to calorieking.com.au
- Flat White with skim milk (small) 285 kJ/68 cal, 9.5g carbs, 0.2g fat
- Flat White with skim milk (large) 521 kJ/124 cal, 17.2g carbs, 0.4g fat
- Flat White with whole milk (small) 521 kJ/124 cal, 8.8g carbs, 7g fat
- Flat White with whole milk (large) 945 kJ/225 cal, 16g carbs, 12.8g fat
- Flat White with soy milk (small) 394.8 kJ/94 cal, 10.7g carbs, 4.2g fat
- Flat White with soy milk (large) 718.2 kJ/171 cal, 19.5g carbs, 7.6g fat
Pop a sugar into that and you'll need to add 63 kJ/15 cals and 4g carbs per teaspoon.
It might not sound like a lot on its own but when you add up the daily tally – and, maybe you're having more than one – then it soon adds up.
Coffee, hormones and gaining weight
Caffeine also affects your sleep, and when you don't sleep well your body produces hormones called Leptin and Ghrelin that are known to increase appetite.
Studies show that leptin increases while we sleep and ghrelin decreases. So when our sleep is broken or inadequate those hormones do the opposite. The result? Increased hunger and decreased sense of fullness.
That sense of never quite feeling full is when we start sniffing around for snacks. That will definitely add inches to your waistline.
Hearing that your daily coffee could be causing you to gain weight isn't news that will land well, but if you keep track of your stress levels, work on reducing your intake and aim for as little caffeine a day then like Weaver's client, you might be able to reduce your weight and gain more energy.
"My clients will tell you that, when it is warranted, I often ask them to give up caffeine completely for four weeks," says Weaver. "They are often shocked by how much more energy they have without caffeine in their lives."