Tessa Munt, Liberal Democrat MP for Wells and Somerset, took the Live Below the Line challenge for Send a Cow in 2014. As part of our 2015 campaign we revisit her experience

As I looked at the diary for my busy week ahead in London, I was just beginning to regret having accepted the challenge all those weeks ago, when March seemed such a long way off. Like many people, I take the almost 24/7 availability of food and drink for granted.

I love my food, enjoy fresh fruit and vegetables, but my weakness is chocolate. But none of that this week! I've had to plan what I'm going to eat, day by day. And remember not to take a biscuit when the plate was passed round the office.

Breakfast isn’t too bad - I've halved my usual two bananas at the start of the day. And instead of eating before I leave, I take one with me into work. That way, I can wait till my tummy rumbles before I have my breakfast, which shortens the long gap till supper.

I realise I'm very lucky that I only drink boiling water. The whole day's budget could have been blown in one go if I was a coffee or tea. I let the nibbles go past me at an event, pleased that I'd remembered my challenge and hadn't absent-mindedly taken one. But then I was ashamed to realise that my guest was a 10 year old who lives with the real challenge of Type 1 Diabetes. She has to watch everything she eats, every single day of her life.

   Tessa, pictured at home in 2014

I had forgotten that in almost every shop in London, vegetables are sold in at least one layer of plastic! Since I don’t have time to get to a market this means buying in bulk.

A punnet of mushrooms, eight onions, six carrots, five courgettes - if you're single, as I am during the week, it’s likely there'll be waste.

You can buy other basics, like rice, in huge quantities at relatively low prices, but if you haven't much money, it's a fair slug of cash up front from your household budget.

So I suppose I 'cheated' as I bought my fruit and veg and worked out the cost of each item. And I had rice, noodles and pasta from home, popped them on the scales and worked out the cost of each meal.

This week has been tough. The almost constant feeling of being empty wasn’t pleasant. But for millions of people, living ‘below the line’ is reality, and this can’t be right.

First published in the Daily Mirror 13 March 2014