The slump after lunch and the sweet craving an hour later may be the same story, told twice

What a big, starchy lunch does to the sugar in your blood, and two plant ingredients researchers have been looking at.

Take someone like Claire, 52. She runs the bookings desk at a builders' merchant in Leicester, and on Tuesdays lunch is whatever the bakery across the road has left: a cheese and pickle baguette, a bag of crisps, a can of something fizzy because it's been that sort of morning.

By half past two the spreadsheet has started to swim. She reads the same row three times. Her eyelids feel the way they do on a long train journey, and the radiator by her desk isn't helping.

At about quarter past three she's at the kettle, and her hand is in the biscuit tin before she's decided anything. She isn't hungry. She ate an hour ago. It's more of a tug than an appetite.

By five she has a burst of energy she could have used at two.

She puts it down to being in her fifties, and to the fact that half the office seems to wilt after lunch too. She's probably right that it's common. Whether it's simply age is another question.

Claire is an illustrative example, not a customer.

Count how many of these sound like your afternoon

Be honest. Nobody's checking.

• You feel heavy and slow within an hour of a big lunch.
• Not long after eating, you want something sweet, even though you're full.
• Your energy comes in waves through the day: a lift, a drop, another lift.
• A coffee or a biscuit is how you get through the afternoon.
• A pasta or sandwich lunch flattens you more than eggs or a salad does.
• You're hungry again sooner than the size of the meal says you should be.

If you counted two or three, you're in very large company.

What if these are connected?

Each one feels like its own small annoyance. The slump is tiredness. The craving is willpower. The ups and downs are just how the day goes.

But look at when they turn up. Most of them cluster in the couple of hours after a meal, and they're usually stronger after some meals than others. That timing is a clue.

What a big lunch does to the sugar in your blood

Most of a baguette, a bowl of pasta or a jacket potato is starch. Starch is long chains of glucose, and your gut is very good at snipping those chains apart. Within an hour or so, a lot of glucose can arrive in your bloodstream at once.

Your body doesn't like leaving it there. It gets to work moving that sugar out of your blood and into your cells, where it's burned for energy or put away for later. After a big, fast rise, the clear-up can be brisk too, and the level can come back down quickly.

That's the wave: a steep climb after eating, then a quicker fall. For many people the fall is when the afternoon goes heavy and the biscuit tin starts calling. A lot of fuel has arrived and left in a short window, and your body nudges you to top up.

None of this means anything is wrong. It's ordinary physiology, and it happens in everyone to some degree. The size of the wave depends a lot on what was on the plate, how much of it there was, and what came with it. Fibre, protein and fat slow things down. A white baguette and a fizzy drink do the opposite.

Why the usual fixes don't really touch it

Most of us already have a routine for the afternoon. Each of these makes sense, and some of them help a bit. None of them changes much about the wave itself.

The habits that do help are dull and worth keeping: build meals around protein and vegetables, go easy on white bread and fizzy drinks, and take a short walk after eating when you can. What follows doesn't replace any of that. It's something you could add to the meals you were going to eat anyway.

What's been studied: cinnamon, and a yellow plant compound called berberine

Which is where cinnamon comes in. Yes, the one on the spice rack. It's not the most riveting answer to a question about biology, but it has a longer research record than you'd expect from something that lives next to the nutmeg.

The published trials on cinnamon supplements have been pooled into umbrella reviews, which are reviews of the reviews. Most of that work looks at two sets of compounds in the bark: cinnamaldehyde and polyphenols.

Berberine is a bright yellow compound found in the roots and bark of plants such as barberry. It has its own record of published research, looked at from a different angle to cinnamon's.

But it can't be just any cinnamon

Here's the catch. Most of what's sold as cinnamon in the UK, in jars and in cheap capsules alike, is cassia (Cinnamomum cassia). It comes from a different tree to true Ceylon cinnamon (Cinnamomum verum), with a more bitter bark.

Cassia also carries far more coumarin, a natural compound Europe's food safety authority (EFSA) advises limiting. A pinch on your porridge is one thing. Taking it every day, in quantity, is another.

The second catch is strength. Subgroup analyses suggest higher cinnamon doses tend to show a larger effect, which is part of why dose and standardisation matter. A capsule of ground bark could hold almost anything. A standardised extract is measured for its active compounds, so each capsule carries the same amount.

Then there's the label. A "proprietary blend" lists the ingredients without saying how much of each went in. And how much of each went in is exactly the number you'd want to see.

If the dose matters, the dose should be in writing.

So if you were choosing one, here's what to look for on the label:

1. 1True Ceylon (Cinnamomum verum), with cassia nowhere on the label.
2. 2A standardised extract, so the active compounds are measured.
3. 3Every dose stated, with no proprietary blend.
4. 4Berberine in the same formula, since it has research of its own.

So we made one with all four

We're Matter, a UK supplement company. You might know us for Daily Beets. When we went looking at the cinnamon on sale, we kept finding cassia labelled simply as "cinnamon", ground bark with nothing measured, and doses tucked inside blends. We couldn't find one we'd take ourselves, so we made it.

Matter Ceylon Cinnamon + Berberine

• 1,000mg Ceylon cinnamon extract (Cinnamomum verum), standardised to cinnamaldehyde and polyphenols
• 500mg berberine HCl
• 2 capsules with a meal · 60 capsules a bag
• No proprietary blend · Non-GMO · Gluten-free

True Ceylon, not cassiaStandardised extractEvery dose stated

It's a food supplement for the hours after a meal, the ones this article has been about. Taken daily with a meal, it supports healthy blood sugar already within the normal range, as part of everyday metabolic wellness. It isn't made for a diagnosed condition, and it doesn't replace anything your GP has you on.

What to expect

1. Day oneTwo capsules with a meal. Take them with your biggest meal of the day, usually lunch or dinner. That's the whole routine.
2. The first monthA bag of 60 lasts 30 days. The published research on cinnamon and berberine as ingredients generally covers several weeks of consistent daily use, so this is a habit to keep up for a while.
3. What we won't doPut a number on it. Everyone's different, and this formula hasn't itself been clinically tested, so we won't promise you a timeline.
4. The good habits stayThe capsules go alongside sensible meals and the walk after lunch, not instead of them.
5. Who it isn't forIt's not intended for pregnant or breastfeeding women, or under-18s. If you take prescription medication, especially for blood sugar or cholesterol, check with your GP or pharmacist first.

Back to Claire's desk

Claire's lunches aren't going to change much. The bakery is still across the road, and Tuesdays are still Tuesdays. What she can choose is what she does around them.

She could carry on as she is: a coffee for the slump, the biscuit tin for the pull, and a quiet assumption that afternoons are simply like this now. Plenty of people do.

Or she could keep the sensible changes, add two capsules of true Ceylon cinnamon and berberine to the meal she was having anyway, and give it a few weeks before making up her mind.

Two ways to spend the next few afternoons

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