Do you wake up everyday feeling tired? And do you find yourself picking up infection if someone so much as mentions they've been feeling a teeny bit unwell?
Welcome to the rundown club - the secret handshake is actually a huge yawn and maybe some tears and the must-have accessory is a hot water bottle.
But the thing is, you can be sparky, sprightly and full of energy again quicker than you can say I-wish-I-was-Miranda-Kerr - all you have to do is follow this advice from nutritionist supreme Kim Pearson.
1. Invest in a pro-biotic. "Not necessarily one of those milky ones," says Kim, "but a high strength supplement. It's estimated 70 - 80% of the immune system is in the gut so ensuring you have the right bacteria there will have a huge impact on your over all health."
2. Stock up on supplements. "Specifically I'd recommend vitamins A, C, E, zinc and selenium," says Kim. "Vitamin D is also crucial for making sure the body is functioning the way it should be."
3. Get garlic. "Garlic contains Allicin which really improves immune system function - you can either eat garlic or take a garlic supplement," says Kim.
4. Stay away from immune system suppressors. Kim lists these as (sorry, you won't love this) alcohol, sugar and stress.
5. Eat fruit and vegetables like they're going out of fashion. "Especially intensely coloured ones like sweet potatoes, carrots and leafy greens," says Kim. "Citrus fruits are brilliant too."