As we head deeper into the cold winter months – and enter a hectic Christmas party period – many of us will be feeling sub-par.

Whether it’s regular sniffles, low mood, dull skin or near-constant tiredness, we often blame ailments on a mix of poor weather, festive stress and pesky germs in heated offices. But when can common winter symptoms be a sign of something deeper going on – specifically, that your body is lacking in a particular vitamin or nutrient it needs to work properly?

According to Erin Viljoen, nutritional therapist at W-Wellness, common winter complaints are often a signal that your immune system needs a helping hand. She’s identified the six most common gripes she hears about and exactly what they mean for your nutrient levels. Here’s her handy cheat sheet for what Christmas niggles might actually be signalling about your health.

Persistent fatigue and low energy levels

We all know the feeling of festive fatigue: too many late nights, dancefloor boogies and, let’s be honest, Christmas cocktails. However, if the general tiredness fails to shift after a few early nights, it can point to a deficiency in vitamin D, iron, vitamin B12 or folate. According to Viljoen, ‘these nutrients are vital for maintaining energy levels and when you’re lacking them, your body can struggle to function at its best.’

‘Vitamin D, which we get much less of in the winter due to reduced daylight hours, plays a huge role in energy and immune function. Iron is also essential for oxygenating your muscles and tissues, and without it, your body might feel sluggish.’

‘Meanwhile, vitamin B12 and folate are both crucial for red blood cell production, and when they’ve dipped, you may therefore feel exhausted and low in energy. All these deficiencies can be identified by a blood test, so if you’re suffering from persistent fatigue, ask your doctor to check your nutrient levels.’

Mood changes or low mood

Sure, we all feel a bit moody when we’re hungover. But if your mood is consistently low or you’ve noticed a real shift, it could mean you’re deficient in vitamin D, omega-3 and B vitamins, which all play key roles in supporting mental clarity.

‘Vitamin D is especially important,’ Viljoen explains, ‘because it helps produce serotonin, the ‘feel-good’ hormone. Omega-3s, meanwhile, which are found in fish and flaxseeds, are essential for brain function and can help reduce symptoms of depression. B vitamins like B6, B12 and folate can help support your mood and reduce feelings of stress and anxiety.’

‘If you’re noticing that your mood isn’t lifting, even with plenty of rest, it might be time to give your diet a closer look,’ she says. ‘Adding some supplements to boost these essential nutrients can help you feel more balanced and positive during the winter months.’

Frequent infections and slow recoveries

Colds, flu and other snuffles spread faster and easier in winter, but if you’re struggling to bounce back or suffering regular bouts of illness, it can indicate a lack of vitamin D, zinc or iron in your system. ‘These nutrients are crucial for supporting your immune system,’ Viljoen advises. ‘Without them, your body might struggle to fight off illnesses as efficiently.’

‘Vitamin D helps regulate immune function,’ she explains, ‘especially in the winter when we don’t get as much sun. Zinc is a powerful antioxidant that helps your body fight off bacteria and viruses, while iron supports the production of healthy red blood cells and transports oxygen throughout the body.’

Muscle aches, weakness or joint pain

Waking up every morning with that post-gym ache, even when the heaviest thing you’ve lifted is a mince pie? According to Viljoen, persistent pains and discomfort might point to a vitamin D or magnesium deficiency, both of which shouldn’t be passed off as ‘getting older’.

‘Vitamin D helps with calcium absorption,’ Viljoen explains, ‘which is key for strong bones. Magnesium, meanwhile, supports muscle function and relaxation. A low level of either can lead to muscle cramps, joint pain and feelings of stiffness.’

‘If the aches are sticking around, consider a supplement to support your nutrient levels. Your body deserves to feel strong and supported year-round.’

Dry skin or brittle hair and nails

Skin naturally dries out in winter, however if you’re experiencing persistent flakiness and weak nails, it’s often a sign of vitamin D, zinc or omega-3 deficiency.

According to Viljoen, ‘vitamin D supports skin regeneration and hydration, while zinc is important for healthy skin cell turnover and wound healing. Omega-3 fatty acids help keep your skin moisturised from the inside, and support its elasticity.’

Cold hands and feet

We all know that feeling of frosty fingers and toes after wandering round the Christmas market. But if you’re struggling with them more generally – particularly when you’re inside – it can suggest you're lacking in iron, iodine or selenium, all of which help regulate your body’s temperature and support healthy circulation.

‘Iron helps your body produce red blood cells that carry oxygen throughout your system,’ Viljoen says, ‘while iodine and selenium are vital for thyroid health. A deficiency in either can affect your metabolism, leading to slower body temperature regulation and cold extremities.’