Our teeth start their life white as snow but they are exposed repeatedly to different staining elements. For example every cup of coffee and tea contains substances that can stain our teeth. And there are many others. The aging process also darkens our teeth as the enameled surface gets thinner and more translucent, gradually exposing the darker interior layer called dentin. 
Although there are dental procedures that can whiten our supposedly pearly whites, they can be expensive. Others resort to bleaches and whitening toothpastes sold over the counter, however there are numerous items in our home and simple techniques that may help without resorting to spending a fortune on dental professional whitening procedures.
The 10 Best Ways To Whiten Your Yellowish Teeth Naturally
1. Oil Pulling – take a spoonful of either olive, sesame or coconut oil into the mouth and swish it around for 15-20 minutes each morning. It can be a little tedious so do this while you are doing something else. Oil pulling is considered not only to whiten teeth and support gum health, but may also have other super health benefits and is claimed by some to actually heal dental cavities!
2. Strawberries – Malic acid, an enzyme added to several whitening toothpastes also occurs naturally in strawberries.  Eat strawberries on a regular basis; slowly munching up the fruits to mash the fruit juices well with your teeth. Or better yet, cut up the fruit in two and stroke the other half along the teeth before eating. Experts also claim that the fibers present in strawberries act like an organic wiper, eliminating bad microorganisms present in the entire oral cavity. Just remember to rinse your mouth or brush your teeth right your strawberry teeth bleaching session because the fruit also contains glucose and acids that might pose a risk of tooth decay.
3. A Carrot a Day Keeps the Plaque Away – Carrots are good for eyes and also for your teeth. Rich in Vitamin C, this carotene-packed vegetable helps prevent the occurrence of periodontal conditions such as gingivitis. The fibrous nature of carrots acts like a natural stain remover because it helps clean the surfaces and hinder accumulation of plaque.  Carrots are not as acidic as other vitamin C-rich fruits and vegetables, thereby allowing you to eat them whenever you want.
4. Activated Charcoal Powder – This one may sound crazy (it’s just about the blackest substance on the planet!) – but activated charcoal has received very good reports as a tooth whitening powder. Simply brush the teeth using the powder as a toothpaste. All the black washes away leaving the teeth feeling cleaner, smoother and noticeably whiter. It’s also reported to assist with oral health. Be very careful not to get it on clothes, bathroom grout etc and wash it away thoroughly in the sink as it leaves stains.
5. Hydrogen Peroxide – If you were to look at the ingredients list of the commonly-found teeth whitening strips, you will find that the active ingredient is hydrogen peroxide. A 3% solution of hydrogen peroxide is considered safe for oral use. Typical method – 2 tablespoons (30ml) of hydrogen peroxide can be swished around the mouth for around 1 minute as a mouthwash. Rinse thoroughly. 2 teaspoons of peroxide can also be mixed with 3 teaspoons of baking soda to form a paste which can be used as toothpaste once a week. 
6. Baking Soda – Ever noticed that baking soda is present in the majority of whitening toothpastes? This is because baking soda is an amazing kitchen item that does everything, from neutralizing the acid level of teeth to eliminating the discolorations accumulated over time of consuming caffeine.  Experts agree that baking soda is one the most powerful, safest and cheapest whitening element available in the market. You can apply it on top of your toothpaste or brush it alone- cleansing and whitening as you scrub a tiny spread on your discolored enamels. Brush baking soda like you normally brush your teeth maximum of 3x a week. The key is consistency.
7. Drink Using A Straw – Tea, coffee and other drinks have the capacity to stain your teeth. Red wines are also capable of leaving unwanted stains on your beloved enamels. From coffee to cocktails, we are exposing our teeth to all kinds of chromogenic elements. (You can impress your friends with that word!) Drinking from a straw can diminish the amount the drink contacts your teeth. Looks childish? We think having stained teeth looks worse. For eco points, buy a stainless steel re-useable straw and skip the disposable plastic kind.
8. Stop Smoking – Kind of obvious this one, but tobacco smoking is a sure short-cut to yellowed teeth. The day you stop is the day that the yellow stains can begin to fade.
9. Back to Basics: Brush And Floss – Another obvious one but good brushing simply helps. There is no excuse acceptable as to why one should not brush their teeth regularly (unless specifically instructed otherwise by the dentist i.e. for bleeding gums, etc.) Remember to brush your teeth with gentle strokes after meals using a soft-bristled brush and floss daily. Flossing takes away the stubborn particles lodged in between teeth. It won’t hurt to carry a box of toothpicks also – especially the tea tree variety, as these can not only clean the teeth but the tea tree has a noted antibacterial action.
10. Swish Your Mouth With Water After Eating/Drinking – Really simple and yet super effective: The importance of rinsing your oral cavity with water every after eating and drinking is that many of the remnants remained inside will be flushed out, thereby preventing further discoloration and possibly limiting decay!  This will also remove much of the sugar from the mouth after eating something sweet, thereby diminishing the bacterial attack on the mouth that sugar causes. Learning this principle, we expect that you now pledge to rinse your mouth the moment you are done with your morning coffee. Rinsing is not an elaborate step; all you have to do is swish drinking water vigorously inside your oral cavity and then spit it out.
 “Dental Health and Tooth Discoloration.” Oral Care. Web MD. N.p., n.d. Web. 24 July 2013.http://www.webmd.com/oral-health/guide/tooth-discoloration
 Mumbi, Mariah. “10 home remedies for whiter teeth.” Lifestyle. Lifestyle Magazine. N.p., 23 Apr. 2013. Web. 24 July 2013. http://www.capitalfm.co.ke/lifestyle/2013/04/23/10-home-remedies-for-whiter-teeth/
 “Natural Teeth Whitening Solutions.” The Dr. Oz Show. N.p., 2 Dec. 2010. Web. 24 July 2013.http://www.doctoroz.com/videos/natural-teeth-whitening-solutions
 “Hydrogen peroxide.” Household Chemicals. Wikipedia. N.p., n.d. Web. 24 July 2013.http://en.wikipedia.org/wiki/Hydrogen_peroxide