When you're trying to downsize, you can get so caught up in kilojoule counting and cravings, it's often impossible to step back and pinpoint why you're not quite getting there. The expert-endorsed fix: a food diary.

"It helps identify areas for improvement and unhealthy habits, and keep track of food choices," says Mary Ellen Bingham, a nutrition counsellor.

The problem is, on our busiest, most emotional days we don't have time to record every bite. To see what would happen if we did, we asked three women with very different lives to track everything they ate during the 24 most stressful hours of their week. Then we called in the experts to analyse their dietary downfalls. What you learn from their advice may stop you from hiring a body double at your next pool party.

THE COMFORT-FOOD CRAVER

Name Jenai Cohen
Age 34
Occupation Part-time ER doctor
Height 155cm
Starting weight 58kg
Goal weight 53kg
Biggest challenge Her erratic work schedule and infant son leave Cohen with little time for balanced meals
The experts Keri Gans, dietitian and personal trainer Wayne Westcott, author of Get Stronger, Feel Younger and a fitness research director

HER TOUGHEST DAY - Sunday night into Monday
10pm: I pull an overnight shift once a week, so my day starts the evening before. My eating schedule is pretty regular except for then, but I need energy to get through the night, so I eat breakfast before I go: a Belgian waffle with butter and maple syrup and a latte with skim milk.
Gans says She'll burn through this high-sugar, low-protein meal in no time. Swap it for low-fat yoghurt with berries and high-fibre cereal.

3am: Feeling sluggish at work. I should have a salad, but I'm craving comfort food. A nurse has brought in a huge bowl of egg salad, and I can't resist. I spread a spoonful on wholemeal bread and follow it with a small piece of chocolate.
Gans says ''If Jenai craves comfort food during her night shift, she needs to bring her own. Options:

• Make an egg salad with hard-boiled eggs and low-fat mayo
  Snack on fruit such as berries, to satisfy her sweet tooth
  Make instant porridge with low-fat milk and cinnamon
  Nuke a sweet potato and have it with low-fat yoghurt''

7am: Shift's over; I drive home in a sleep-deprived daze, kiss husband and baby, then collapse into bed.

Noon: Zero appetite when I wake up.
Gans says Understandable, but she should eat something - she needs to kickstart her metabolism if she wants to burn more kilojoules, even if it's just a bowl of high-fibre cereal with low-fat milk.

4pm: Finally hungry. Grab a box of sultanas and three crackers.
Gans says Choose nutrient-dense snacks. A fibre-protein combo that'll keep her fuller longer: a high-fibre, wholegrain cracker, such as Ryvita, with reduced-fat cheese.

5pm: Too tired to cook. On Mondays, we usually have takeaway. Tonight I order pizza and chase it with a chocolate chip cookie.
Gans says Her meals should be balanced and include more greens: half a plate of vegies, a quarter of a plate of high-fibre carbs, and a quarter of a plate of protein. She could whip this up in very little time by stocking up on the following: a ready-to-eat bbq chook wholegrain couscous or pasta several packs of frozen vegies to steam, boil or microwave.

7pm: I usually work out while my son is napping. But the day after my night shift, I manage to squeeze in only 30 minutes on my exercise bike and some ab work.
Westcott says When she's time-crunched, Jenai would be better off skipping cardio and focusing on strength training, which increases muscle mass and metabolism, allowing her to burn more kilojoules. At home, she can do dumbbell squats, push-ups, bicep curls and tricep extensions (eight to 12 in 60 seconds, to the point of fatigue).

8:30pm: Have a glass of white wine. I deserve a treat; wine or ice-cream!
Gans says Pick the wine and ditch the ice-cream. The former is actually a good choice because it's fairly low in kilojoules (around 400 per glass) and you can savour it.

BOTTOM LINE Jenai's problem isn't her schedule; it's her habit of needing comfort food when she's tired or stressed. Her best solution: prepare healthier versions of her favourites. She should make a list of what she craves and look for healthy, low-kJ options (flip this mag over for a cooking special that has just that).

JENAI'S TAKE Keeping a food diary has helped me feel more accountable to myself. Eating right takes a lot of discipline, but I feel more energised now, and I realise that it's possible to eat comfort food that's also good for me. The sacrifices are worth it: I want to be the mum running after her toddler on the beach in a bikini!

THE HABITUAL MEAL-SKIPPER

Name Courtney Hanrahan
Age 31
Occupation Environmental consultant
Height 178cm
Starting weight 93kg
Goal weight 80kg
Biggest challenge Frequent travel (business and pleasure) derails her diet and fitness routine
The experts Dr Melina Jampolis, physician nutrition specialist and author of The No Time to Lose Diet; Jennifer Jolly, certified personal trainer and boot-camp coach

HER TOUGHEST DAY Saturday
10am After a late night visiting my parents, I wake up feeling famished. In the hotel restaurant, while I'm waiting for my omelette, I pick at my husband's hot chips and end up devouring half of them. Still hungry when my breakfast arrives, I hit the buffet for a muffin with butter and cream cheese and chase it with a coffee.

Jampolis says Extreme hunger will crush anyone's willpower. Courtney should take the edge off with the first high-protein and/or high-fibre food she can find - in this case, a banana or an apple from the buffet. To ensure there's always a healthy snack on hand, she should stash her own: Artisse Organic Snack Bars Uncle Tobys Bodywise Bars Orgran Fruit Filled Apricot Bars.

Noon Still stuffed from breakfast, I run errands without stopping to eat.
Jampolis says When you break the bank at one meal, it's natural to want to skip the next, but that only perpetuates a cycle of blood-sugar highs and lows. The second that Courtney feels peckish, she should nosh on one of her healthy handbag snacks to steady her energy levels and satisfy her hunger.

2:30pm During the week I'd normally work out now. But I do that drill all week long, so I deserve a break on weekends.
Jolly says She needs to get away from an all-or-nothing attitude towards exercise. When she can't get to the gym, she should do a quick home workout: skipping for two minutes, deep-lunging across the lounge room floor 10 times, then as many push-ups as she can. She might want to buy a watch that monitors heart rate and kilojoules burned (such as the Tech4 Tech4O Accelerometer Pedometer Watch Trail Runner: $135, pedometersaustralia.com) to help motivate herself.

4 pm More errands. And a Diet Coke.
Jampolis says A protein-packed snack like almonds or one of the snack bars listed would give her an infinitely healthier, longer-lasting boost than a nutritionally empty diet soft drink.

6:30pm At an Italian restaurant with my husband, I scarf down two pieces of bread with butter before my Caesar salad arrives. I feel guilty, but dive into chicken marsala and have two glasses of wine anyway. I'm showing no restraint, but I've resisted all week and want to treat myself.
Jampolis says When she's dining out, Courtney should start every meal with either: salad dressed in olive oil and vinegar a bowl of broth-based soup.

BOTTOM LINE Imbalanced meals cause Courtney to overeat. Without a healthy mix of high-fibre carbs, protein and fruits and vegies, she doesn't stay full for long and winds up overeating. Having high-protein, low-kilojoule snacks between healthy meals will speed up her metabolism and help her avoid food binges.

COURTNEY'S TAKE Weekends were tough because I lacked a routine, but after almost eight weeks, I've found that eating several times a day instead of saving up my kilojoules for a pig-out gives me more energy, and I'm not hungry in between meals. I end up eating less overall!

THE BAR-FOOD ADDICT

Name Ragni Agarwal
Age 26
Occupation Graphic designer
Height 162cm
Starting weight 67kg
Goal weight 57kg
Biggest challenge Going out three to four nights a week with friends sabotages her diet and fitness routines
The experts Mary Ellen Bingham, dietitian and nutrition counsellor Nicole Glor, group exercise instructor and developer of fitness DVDs available at nikkifitness.com

HER TOUGHEST DAY Friday

7:50am Drag myself out of bed and head to the gym to hit the cross trainer. I was out late with friends again last night. We go out three or four times a week - hey, I'm 26 and single!

Bingham says Ragni has to start fuelling up before exercise or she'll be ravenous later. A smart option: half a wholemeal English muffin with peanut butter or half a banana.
Glor says Multitasking moves, like a bicep curl/lunge combo, will work every major muscle group and raise her heart rate quickly.

9am Grab a coffee and a wholemeal toastie with low-fat cheese and a vegetarian pattie. I try to start my day healthy because I tend to fall off the wagon on weekends.
Bingham says Good choices - protein and carbs help you feel full longer. She could try: a 2-egg omelette with half a cup low-fat cottage cheese

10am Down another coffee and about four glasses of water. I drink a lot at my desk all day so I won't get hungry and snack.
Bingham says Drinking water is good, but Ragni can't rely on liquids alone - hunger will creep up on her. When it hits she should have one of these snacks: a handful of peanuts or almonds low-fat yoghurt with a couple of wholegrain crackers a Carman's Muesli Bar wholegrain crackers with hummus

2:45pm For lunch, I hit the salad bar at the deli next door. OK, I confess I go a little overboard with the cheese, chicken and creamy dressing - people laugh and ask if I want any lettuce with my croutons.
Bingham says Her dipping energy levels are making her crave carbs, which explains the croutons. A wholemeal roll or multigrain bread would be better. She needs to bulk up on vegies, even if they're part of a sandwich.

4:50pm Last night is catching up with me again; grab a medium skim-milk latte.
Bingham says Ragni should limit herself to two coffees a day and give her body a boost with food instead. One of the snacks mentioned before or wholemeal crackers and an apple with peanut butter would perk her up.

6pm Happy hour - what I've been saving up kilojoules for! After two vodka and Diet Cokes, I go for the nachos and potato wedges.
Bingham says Saving kilojoules might seem like a good strategy, but she's filling up on alcohol, sugar and fat and missing the vitamins, minerals, antioxidants and complex carbs her body needs. She should have something healthy beforehand, like a grilled chicken sandwich on multigrain bread with grainy mustard, so she doesn't feel tempted to pig out after a few drinks.

9:30pm Still going strong: I polish off two more vodka and Diet Cokes.
Bingham says All those drinks add up. Even when using diet drinks as mixers, she's drinking about 1000 empty kJs. Ragni has to go out less or drink less when she's out.

BOTTOM LINE Ragni skimps on food all day and then goes crazy at night. She should redistribute kilojoules so she's eating about every four hours to fuel her body. Her energy will be higher and her body will actually be more efficient at burning kilojoules when it's not hit with an excess of fat and kJs all at once.

RAGNI'S TAKE I have a hard time regulating drinks when I'm out, so I'm focusing on eating more healthy food through the day, which is giving me more energy and making it easier not to eat junk late at night. My friends help by not offering to share their wedges or nachos and by congratulating me when I make it to the end of a night out without eating any junk.