Every year, cold and flu season descends upon us and we tend to believe we’re powerless to stop the onslaught of germs. Many of us are on high alert because we know that germs are swirling about! There are ways to build our immune system and keep our bodies on guard so that we can sidestep the possibility of catching something this year.

Here are my top five strategies to help you do just that:

1. Avoid sugar

We already know that processed and refined sugars contribute to obesity, diabetes, cancer and of course, tooth decay. But here’s another reason to skip it: sugar suppresses our immune system, leaving us more susceptible to infections like colds and flu. Excess sugars and refined carbohydrates also affect our cells’ ability to engulf bacteria. Sugar affects our gut bacteria and disrupts our probiotic balance. About 70 percent of our immune system is located in and around our intestines in our gut-associated lymphatic tissue, or GALT. This means when our digestion isn’t functioning properly, our immune system won’t perform at optimum levels either.

Lastly, glucose (aka sugar) and Vitamin C have similar chemical structures, so when we eat cookies, cake and candy, those sugars compete with vitamin C for entry into the cell. Unfortunately, the insulin receptors on our cells favor glucose over vitamin C, so if there is more glucose around, there is going to be less vitamin C allowed in. Vitamin C is a popular nutrient used to boost the immune system, but if you’re consuming sugar along with it, you’re not going to receive those immune-enhancing benefits.

2. Get enough sleep

Lack of sleep is more than an inconvenience—it can seriously affect your short-term and long-term health. As we sleep, our bodies relax, repair, and regenerate, and if that isn’t occurring we become susceptible to a wide array of health issues including weight gain, memory problems and a weakened immune system.

Evidence shows that a good night’s sleep boosts immune function and helps filter T-cells into our lymph nodes. Our lymphatic system is essential for defending our bodies from external invaders, so sleeping well can help you prevent colds and flu.

If you’re having trouble sleeping, it helps to set a regular schedule (including waking and going to bed at the same time), to sleep in complete darkness, and implement a relaxing nighttime tradition such as taking a bath, meditating, reading, or having a cup of tea. And don’t forget to turn off all electronic devices an hour before bed!

3. Reduce or limit stress

Stress seems to be unavoidable but learning to manage your stress is key. When we’re constantly stressed, it lowers our immunity and affects our ability to shut down the inflammatory processes that lead to infections. In one study on stress and immunity, researchers exposed volunteers to viruses after they had experienced prolonged life stress. Researchers found that these volunteers were more susceptible to colds and produced more pro-inflammatory compounds.

Reducing or limiting stress is easier said than done, but I encourage you to explore the stress-busting activities that work best for you—whether that’s attending a yoga class, walking in nature, spending time with family, or being creative.

4. Eat immune-boosting foods

I’m a nutritionist, so you might have assumed this would be my first point of advice. Food is incredibly powerful, but if we’re insanely stressed out and barely sleeping, food can only do so much.

A good diet loaded with plant-based foods is one of your best defenses against colds and flu. And I don’t just mean you should eat healthfully the moment you feel a cold coming on. You must make a regular commitment to eating produce, nuts and seeds, beans and legumes, gluten-free whole grains, and organic animal products and also drinking plenty of water.

Some of the immune-boosting foods I recommend are:

  • Cauliflower, bell pepper, dark leafy greens, citrus—these are rich in vitamin C, an immune-booster.
  • Eggs and fish—these are high in vitamin D. Our immune cells have Vitamin D receptors, so this vitamin can help regulate our immune system.
  • Fermented foods like sauerkraut, kimchee and miso—these help to boost the immune system and keep your gut healthy.
  • Hemp seeds, almonds, sunflower seeds, organic meat—these are rich in protein, and protein is essential for healing and repair.

5. Sweat it out

Having a good sweat can help you excrete toxins through your skin and raise your core body temperature, which will kill off potential pathogens. You can also visit an infrared sauna or attend a hot yoga class.

Regular exercise can also help prevent colds and flu. In a study of postmenopausal women, those who exercised five times a week for an entire year reduced the number of colds and flu. Incorporating exercise into your life also improves bone health, cardiovascular health and can benefit people with cancer (an immune disease), so discover the physical activities you love and practice them every week.

When we make good health a priority, we can arm ourselves with all of the elements our bodies need to strengthen immunity.

Incorporate these tips into your daily life and cold and flu season just might pass you by this year.