The link between sinus issues and intestinal problems is related to the structure of the body and to the close relationship between the lungs and the colon. The skin or membrane that lines the wall of the sinus cavities, the respiratory tract and the gastrointestinal tract are ONE in the same ... just as the skin on your arm is the same skin that covers your toes .
The physical body is structured like a donut. A donut has two outside borders - the larger ring and the smaller ring. The outside ring or border around the donut represents the skin that covers the outside of the body. This skin is the protective border located "outside on the outside", and this skin acts as a barrier to the external environment we live in. The ring around the inside hole of the donut represents the skin or mucosal membrane that lines the tube that goes through our body, from the tip of the nose to the rectum - including the lining of all cavities that branch out from that tube (sinuses, mouth, respiratory tract, stomach, intestinal tract). This skin is the protective boarder referred to as the "outside on the inside", and it acts as a barrier to the external environment that comes through or into the inside of the body - where bacteria, pollen, and harmful substances come in via air through the nose and mouth and in the foods that we consume. Thus, skin and mucus membrane share the same protective function and are physically and structurally related, like brother/sister.
In Chinese Medicine the skin is considered an organ - actually, the skin is considered to be part of the lungs. All skin, including mucosal membrane lining the respiratory and gastrointestinal tracts, is protective yet porous. The skin has a dual purpose. It must protect our sacred body from harmful influences that exist in the outside environment. It is also one of the primary means by which the body absorbs nutrients and eliminates toxic waste and by-products of metabolism. This is especially true of the skin that lines the respiratory and gastrointestinal tracts. The "wei qi" or "defensive immune system" is located just beneath the epidermis or outer layer of skin. Whenever a harmful substance penetrates through the protective outer layer of the skin, the "wei qi" must spring into action in order to keep the body pure and the vital organs safe from infection. The response of this sophisticated alarm system is always "allergic reaction". All immune responses are allergic responses. Whether the immune system is responding to an incoming virus, bacteria or pollen in the respiratory tract or to a substance that cannot be digested in the gastrointestinal tract (toxic chemicals, foods and foreign objects), the response is always an allergic response.
Most people assume that sinus problems are due to some disturbance in the respiratory tract and/or to an infection from the outside environment. They treat with anti-histamines or antibiotics but find that relief is only temporary. Most sinus problems are actually related to allergies - particularly allergic reactions coming from food and drink in the gut. If your gut is plugged up with stuff that cannot be processed, your nose will be plugged up. If you have an allergy to red wine and it is in your gut, your nose will be plugged up. Most people are unaware that they lack certain enzymes for digesting certain foods. When they consume these foods, they cannot be properly digested. The body's immune system correctly identifies the undigested substances as being toxic, so it creates an allergic response. All allergic responses are inflammatory in nature and always affect the brain and cavities in the head in some way and to varying degrees. A common side effect of an allergic response is fluid accumulation in the cavities of the body. In Chinese Medicine "damp accumulation" is identified as an underlying cause of most diseases. Damp becomes a breeding ground for mold, yeast and other opportunistic invaders.
When Mayo Clinic cultured the sinus cavity of individuals with sinusitis and chronic sinus infections, they found that 96% had chronic fungal infections - not a bacterial infection. Yet most doctors prescribe antibiotics. A large percentage of the sinusitis patients who get prescribed antibiotics have side effects such as gastrointestinal problems, skin rashes or sinus headaches. The internal milieu of the body turns into a toxic waste ground of damp accumulation ... leading to chronic allergies and more damp accumulation in the sinuses, ears, lymph glands, colon and urinary tract.
Whenever there is a disturbance in the gut, there will be a disturbance in the sinuses. When you improve digestion and restore health to the intestinal tract, you will have fewer sinus problems. In Chinese Medicine the goal is ALWAYS to improve immunity. The key to improving immunity is to improve digestion. You cannot have good health without having good digestion first. Good digestion clears damp accumulation. Chinese herbal formulas for acute and chronic sinus problems address the underlying allergic response mechanism triggered by irritants from both the respiratory tract and the digestive tract. Chinese Medicine is good medicine.