Winter hair care

Now that the weather is turning colder (and dryer!) it can really mess with your hair. Cold, dry air, wind, and dry artificial heat can all contribute to dryness, static, limp curls and damage!
The answer? MOISTURE! Simple enough answer, right? Right. But getting, and keeping, a proper moisture balance this time of year can be hard.
First, we need to understand a few things. Each individual hair strand is covered by a cuticle. The cuticle looks like shingles on a roof. These shingles protect the inner structure of the hair. In a healthy condition, these shingles will lift under certain conditions to allow moisture in, and close to keep it in under certain conditions. Heat will raise the cuticle. So every time you  take a hot shower or use a blow dryer, you are raising that cuticle. Raising the PH of hair with products also lifts the cuticle. Sulfate shampoos will lift the cuticle and the hair will absorb the shampoo!
Second, we need to understand dew points. The dew point is the air temperature at which the air becomes saturated with water. The warmer it is, the more water air can hold. When the temperatures drop, even if the humidity is high, the dew point will most likely be low, so the air is still dry. What does this mean for your hair? Hair can absorb moisture from the air if there is moisture in the air to absorb. If there isn't a lot of moisture in the air, the air can actually pull moisture from your hair.
Dew points above 60-65F are considered very high. You may have more curl, and more frizz. Dew points between 40-60F are considered normal dews. There is enough moisture to keep curls happy without much frizz. 30-40F are moderately dry. How your hair reacts depends on your hair! It may be enough moisture, it may be slightly dry and you may notice some curl droop. Below 30F is considered dry, Curls may droop, and start to dry out. Below 15F is very dry. Weaker curl patterns may disappear and appear straight.
Third, humectants. Humectants draw water to themselves. Glycerin, honey, propylene glycol, are all humectants. When the air is too dry, these can pull water out of your hair.
So what can you do to keep your hair well moisturized? One of the best things you can do is to keep the air in your home at a comfortable moisture level. I like to use crockpots filled with water set on low. Mostly because they will still work if they develop lime scale. Humidifiers can be simple and just have high, medium, or low settings, or they can be fancy and measure the amount of humidity in the air and keep it a consistent level. You may want to switch to a more moisturizing conditioner. These don't have to be heavy. I really like Generic Value Products Conditioning Balm from Sally's Beauty Supply. It's a Matrix Biolage Conditioning Balm knock-off. It is very thick and moisturizing, but rinses surprisingly clean. Renpure My Pretty Hair Is Parched is light but very moisturizing. Check the WHC Product Reviews blog for reviews on other conditioners. Leave-ins are also a good choice for winter. I actually use one year round, because my hair drinks them up. You can use your rinse-out conditioner. Your co-wash conditioner for a lighter choice, or any other conditioner you choose.
Regular deep conditioning treatments can add a nice boost of moisture. You can choose a conditioner labeled for deep treatments, or you can make your own! It can be as simple as adding some oil to your regular conditioner, or you can use one of a thousand recipes for homemade deep treatments found all over the net! You might want to add heat for extra moisture, or if your hair is low-porosity or course. This will open the cuticle to allow the deep treatment to work better. The spritz and condish method might work well, also. Try to avoid humectants, espeacially in products left in your hair. They may not be a big deal in your low-poo/co-wash or rinse out conditioner, provided you rinse all of your rinse out condish out. Some like to leave some in and use that as thier leave in. For some however, even humectants in thier rinse out products can have an adverse effect.
Keeping the cuticle closed after cleansing and conditioning is important for many reasons. It seals in moisture and protects the hair's cortex, plus, it adds shine! Try not to take super hot showers. Warm water opens the cuticle less and helps prevent moisture loss. Rinsing in cold water closes the cuticle, but in the winter, who wants to do that? Well, one way to do this with out freezing your buns off is to rinse slightly in the warm water from the shower. Then turn the shower to the tub faucet and turn it to cool (it doesn't have to be freezing). Lean forward and cup your hands and bring this water up into your hair to your scalp. You can then scrunch lightly to rinse more conditioner out if you feel you need to. Another option is to use an apple cider vinegar rinse. This returns hair to the proper acidic PH which closes the cuticle. You add anywhere from a teaspoon to 1/4 cup ACV to a cup of water and pour this over your head after rinsing your conditioner. You may then leave this in, or leave it for a few minutes then rinse it out. Just don't do this too often! Using this rinse too much can start to damage your hair.
Sealing with an oil or an oil-containing humectant free product (I like Shea Moisture Curl and Style Milk) can help hold moisture in. After cleansing and conditioning, you can use your oil-free leave in on wet (not damp) hair, then take a small amount of oil (like coconut, extra virgin olive, jojoba...) start with only a drop or 2. Smooth and scrunch or rake, whichever you prefer, through your hair. You could also add a drop or 2 of oil to your oil-free leave in. If you choose to use a humectant free oil-containing product, just apply to wet hair. I also like to scrunch out the crunch of my gel with a few drops of coconut oil in the winter. My hair drinks it up, so after half and hour to an hour, there is no oil detectable on my hair. This acts as sort of an anti-humectant or sealant on dry hair that keeps it from drying out.