Is it just me, or is it hard to believe that October is already halfway over? Trees are shedding their leaves, darkness is coming earlier every night, and we’ve swapped our summer shorts for cozy sweaters. Before we know it, it’ll be 2015 … but let’s not get ahead of ourselves.

First, we need to get through the months ahead. Sure, the last several months of the year can be exciting – the golden days of fall, the fun of Halloween, and the whirlwind of the holiday season – but for many people, they can also be a time of worsening depression and anxiety.

This phenomenon, often called the “winter blues,” is officially known as Seasonal Affective Disorder, or SAD. It’s estimated that at least 11 million Americans suffer from SAD, and an additional 25 million face a milder, but still disruptive, form of the disorder. Those already living with mental illness, such as anxiety disorders, major depression, or bipolar disorder, are especially likely to see their symptoms worsen this time of year.

There’s a lot of information out there about treating and managing seasonal depression/anxiety; suggestions range from (often pricey) home light therapy to antidepressant medications. But we can also take a simpler, inexpensive, and holistic approach to managing the blues associated with less sunlight, colder temperatures, and end-of-year stress.

When I start to notice my anxiety on the rise, I find that these four strategies help me keep everything in check.

• Keep your physical activity level up even as temperatures drop. During the summer months, we tend to get more exercise without even thinking about it, just by being out and about more often. And most of us find workouts to be more enjoyable when we can run, walk, hike, or swim outside. Exercise releases mood-enhancing endorphins, boosts serotonin production, and helps us get a good night’s sleep. Because SAD is tied to decreased serotonin production and disrupted sleep cycles, it’s important to make an effort to stay active during the fall and winter.

• Pay attention to nourishment and keep emotional eating in check. It’s a natural instinct to eat heavier meals this time of year, and one of the symptoms of SAD is increased appetite, particularly for carbohydrates. But before you allow yourself to fall into a five-month pasta coma, remember how crucial nutrition is to maintaining optimal mental and physical health. Do your best to eat a healthy, balanced diet, and to differentiate between cravings and actual hunger.

• Prioritize sunlight and Vitamin D. Vitamin D, which we get primarily from sunlight, is essential to emotional well-being. Additionally, sunlight is important in the regulation of circadian rhythm, or our bodies’ internal clocks. Getting outside in the sun for 10-15 minutes a day (even if it’s cold), and supplementing with vitamin D, can greatly improve mood and help maintain restful, restorative sleep.

• Don’t become a shut-in. Many of us need to fight the urge to “hibernate” all winter. It’s easy to lose motivation to see our friends, to take part in activities we enjoy, or even just leave the house. While it’s tempting to stay curled up under the covers all day, maintaining our hobbies and social life helps us from succumbing to the winter blues.