Emma Bartley’s ongoing struggle to fit into her jeans. This week: is drinking fruit juice really the new "eating a massive slice of chocolate cake"?

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Woop! I’m one sixth of the way to OMG already. The good news is, I’ve had a cold bath every day for the past week, skipped breakfast every day but one, and drunk gallons of black coffee. The bad news is, I’ve only lost 200g – an amount roughly equivalent to the average wee.

In fairness to Venice A. Fulton, I haven’t been following all his advice, particularly with regard to liquid carbs. So this week, in the hope of educating you, the reader and bringing me, the dieter, a renewed focus, Size 13 will look more closely at the eating habits Venice recommends.

As we learnt last week, your daily total carb intake is the biggest factor to affect your success. Venice, who doesn’t care if your carbs come from Coke or from broccoli as long as you don’t consume too many, gives a guideline daily carbohydrate weight for the different levels of diet. I’ve chosen easy WAVE, so I get 120g a day – but who’s seriously going to weigh their carbs? Fortunately, OMG-ers also have an easy-to-remember limit at each of the three meals a day they are supposed to eat. You never eat more than four iPhones’ worth of carbohydrate. Or four BlackBerrys – Venice isn’t brand-loyal, though I wish he’d given the amount in HTCs because I’m sure my phone is skinnier than all my friends’.

Half your plate, he says, should be protein. (I quickly get very bored with chicken, which is the easiest base protein to get hold of at lunchtimes.) The other half should be vegetables, and your four iPhones/five HTCs’ worth of carbs. Some vegetables count as carbs – peas and sweet potatoes, for example. I don’t find it too hard to load up my plate with chicken, chickpeas, tuna and salad and I find I get full quite quickly after having starved from the previous night until about 1pm.

Six Weeks to OMG is not remotely interested in fat: trans fats are bad, says Venice, but low-fat foods are full of sugar and besides, we need the fats found in oily fish such as salmon and mackerel.

The main food he has a problem with is fruit, particularly fruit juice. Fructose (the sugar in fruit) interferes with your body’s insulin production and thus your appetite and fat-burning. So you’re not supposed to eat more than three fruits a day, they must only be with meals and he has divided them up into three groups, indicating which are particularly fructose-y fruits and which are better. Blueberries are quite good, mangoes are quite bad. Smoothies and juices, being liquids, slip down your throat, giving your blood sugar a quick spike but not filling you up in the way that a slower-to-process carb (such as brown rice) would.

This is a revelation to me: I know the carbs in alcohol are bad, but I’ve enjoyed a small glass of grapefruit juice every morning with my porridge for years, and the idea that this is a sin food only makes me want it more. But since it’s fructose and I have it at breakfast time, it goes against everything Venice A stands for. I jettison it… most of the time. One very weak day, I decide (much in the way I used to about Krispy Kremes) “screw it” and down a whole glass. It doesn’t taste sweet, but a look at the carton reveals it contains 17g of sugar per 100ml.

Guiltily, I go on Twitter and admit what I’ve done to @veniceafulton . “Emma, grapefruit juice isn't cheating!” he says. “Your body doesn't know what cheating is. Grapefruit juice can be naughty if it's mixed… with certain drugs, slowing their breakdown in the liver, and building up their blood levels dangerously sometimes. But.. .Apart from that oddity, remember there's no evil food (not even broccoli!). And #6WeeksToOMG  isn't about being ultra strict...or following a guru (I'm far too unwrinkled for one of those!). You're the expert. And bit by bit, you'll get everything sorted.”

I know! Venice A. Fulton addressed me directly, in at least four tweets (he’s greedy with characters even if he has the power to avoid smoothies). And he reminded me of why I’m doing – well, sort of – this diet. It’s OK just to do your best, and it feels as if following some of his advice most of the time will make some sort of difference.

Now I just have to bring myself to start blowing up balloons. Stay tuned on Twitter  and look out for Venice’s toning and stomach-flattening tips next week.

Five weeks to OMG

Weight: 70.8kg

Enthusiasm: Middling - the wine I've been drinking but not counting helps

Waist: forgot to measure, probably not a good idea anyway

Pics: A lot like last week, but more bloated.