concepts

Anti–Inflammatory

Acute inflammation is a normal and healthy part of the body’s immune response; it is needed for healing an injury or fighting an infection. However, chronic inflammation inside our body diminishes our body’s ability to repair itself. Researchers believe inflammation is linked to many chronic diseases such as rheumatoid arthritis, cardiovascular disease, Alzheimer’s and certain cancers. Eye conditions associated with inflammation include age-related macular degeneration, dry eye and uveitis.

An anti-inflammatory diet helps to promote the lowering of overall levels of inflammation in the body. Certain foods can ramp up the body’s inflammatory response while other foods dampen the response. Two essential fatty acids important to the balance of inflammatory response are omega-3 and omega-6. Omega-3’s form the building blocks of a number of anti-inflammatory compounds and lower the production of inflammatory proteins. Foods high in omega-3 fatty acids include oily, cold water fish like mackerel, salmon and black cod. The pro-inflammatory omega-6 fatty acids are found abundantly in corn, safflower and peanut oils, as well as processed and refined foods. The current recommendation is a ratio of one omega-3 fatty acid to four omega-6 fatty acids.

Culinary herbs and spices contain a vast array of powerful phytochemical compounds many which have anti-inflammatory properties. Turmeric is a highly pigmented root noted for both its anti-inflammatory and anti-oxidant attributes.   Turmeric most notably is found in tandoori and curry powders.  Ginger root is a common ingredient in Asian cuisine having both anti-inflammatory and anti-nausea properties. Oregano, basil and rosemary are delicious anti-inflammatory herbs. The phytonutrients allicin and quercetin found in garlic and onions have immunity boosting properties. Antioxidants protect the body from the inflammatory effects of free radicals. Colorful food like berries and peppers, as well as kale, beets and green tea are all excellent sources of antioxidants.  Food high in fiber helps to minimize the inflammatory response that can occur following a rapid increase or decrease in blood sugar levels. Foods high in fiber include raspberries, beans, legumes, vegetables and cinnamon.

While dietary changes are not intended to supplant traditional medical therapies recommended by your doctor, food offers a delicious symphony of nutrients with anti-inflammatory disease-preventive benefits. The researchers at Oregon Health & Science University state that tart cherries have the “highest anti-inflammatory content of any food.” Making smart food choices to keep the immune system in balance will help facilitate health and well being.  According to Emperor Charlemagne in the 9th century, “An herb is the friend of physicians and praise of cooks.” 

Antioxidants

The eyes are highly metabolically active. In fact, the retina has the highest metabolic rate of any tissue in the body and is therefore vulnerable to oxidative injury. The most notable antioxidants which help to support the eye are vitamin C, vitamin E; the carotenoids lutein and zeaxanthin; selenium and phytonutrients. One method of assessing the antioxidant capacity of a particular food is expressed in ORAC units (Oxygen Radical Absorbance Capacity). Spices such as cloves, cinnamon and turmeric have a very high ORAC value. Natural cocoa, coffee and green tea are all great sources of antioxidants and have high ORAC values. Other foods high in antioxidants include berries, nuts, dried fruit, vegetables and beans.

Culinary preparation influences the quantity of antioxidants present in a particular food. Since many antioxidants are found in the peel or outer parts of fruit and vegetables, peeling eliminates a significant portion of antioxidants. When berries are boiled to make jam, the heat denatures the antioxidant capacity of the vitamin C and phytonutrients. Jam has little antioxidant capacity especially when compared to fresh berries. Steaming vegetables retain more antioxidants than boiling in water. The nutrient lutein found in kale is more accessible to our bodies when the plant cell walls are broken down through cooking or pureeing.

Oxidation is a natural process that occurs during normal cellular function as oxygen is needed to produce energy by the cells in our eyes and bodies. Free radical formation is derived from this normal metabolic process and from external sources like x-rays, cigarette smoking, air pollutants and sunlight. 

Free radicals have a strong affinity for electrons and can damage cells and genetic material. To help with the battle against free radicals, every cell in the body creates its own antioxidant enzymes to diffuse free radicals. In addition, we can acquire antioxidants from food. A balance between free radicals and antioxidants is necessary for proper physiological function and to reduce oxidative stress. Oxidative stress is thought to play a role in age-related macular degeneration, age-related cataract formation, glaucoma and other diseases.  Including antioxidant rich foods in your diet everyday will help to reduce the risk or slow the progression of many chronic eye diseases associated with aging. 

Blood Sugar Regulation

Obesity and blood sugar disorders increase the risk for diabetes and cardiovascular disease. In the eye, well controlled blood sugar decreases the risk of age-related macular degeneration (AMD), diabetic retinopathy and cataracts. The key nutritional principles that help to promote blood sugar regulation include eating foods with: a high in dietary fiber content, a low glycemic index and a complete protein.

 

Dietary fiber helps to stabilize blood glucose levels by slowing the absorption of carbohydrates in the gut. Insoluble fiber is nature’s broom, helping to maintain digestive system health. Soluble fiber supports maintenance of healthy blood glucose levels and reduces cholesterol absorption.

 

Glycemic index is a convenient way to measure the relative influence on blood sugar of one food versus a ‘standard’ food. A food that has a low glycemic index will not raise the blood sugar as quickly as food with a high glycemic index. Fish, eggs and leafy green vegetables have a low glycemic index; potatoes, white bread and fruit juice have a high glycemic index. The portion size of the carbohydrate eaten and its glycemic index are used to calculate the glycemic load. When making food choices, reduce the effect of higher glycemic index foods by choosing smaller portions or by combining low glycemic index foods with a protein.

 

Proteins, besides promoting blood sugar regulation, help the body to build, maintain and repair itself. Complete proteins are constructed from 22 amino acids. Animal-based foods such as eggs, meat and fish contain all 22 amino acids. Plant-based foods are sources of incomplete proteins, with the exception of soy and quinoa. However, a complete protein can be built by combining incomplete protein sources. For example: Grains + Legumes (brown rice + red beans); Grains + Nuts + Seeds (whole grain bread + walnuts + sunflower seeds) can be combined to build a complete protein.

 

Well controlled blood sugar clearly promotes long term health and wellness for the eyes and body.

 

Lutein and Zeaxanthin: The Macular Pigments

The xanthophylls lutein (L), and zeaxanthin (Z), are two of more than 600 known naturally occurring carotenoids. Synthesized by plants, these yellow, orange and red carotenoid pigments act to absorb light energy for photosynthesis and to protect the plant from high energy UV light. These pigments serve a similar role in protecting the eye from photo-oxidative stress. The yellow from carotenoid accumulation gives the posterior polar region of the retina its name: Macula Lutea or “yellow spot.”

 

L and Z are fat soluble, essential nutrients in the vitamin A family. An “essential” nutrient is one that must be acquired in the diet since the human body is not able to synthesize it. The isomers L and Z are frequently quantified together and are annotated as “L+Z,” making it difficult to assess which carotenoid is actually present in a particular food. L is found abundantly in leafy green vegetables such as spinach and kale. Sources of Z include corn, paprika, egg yolk and goji berries. The L and Z found in egg yolk is highly bioavailable and preferentially accumulate in the macula. Goji berries are the richest source of plant derived Z. Fat-soluble nutrients is more efficiently absorbed when consumed with a fat. Also, steaming, sautéing or pureeing vegetables will help breakdown plant cell walls, increasing the body’s access to these nutrients. Spinach sautéed with olive oil would be a delicious example!

 

L and Z are found in both the crystalline lens and the macula where they function as a blue light filter and offer protection from light induced oxidative cell damage. Epidemiological evidence has demonstrated a reduction in the risk of progression of Age-related Macular Degeneration(AMD) with higher dietary and plasma levels of L and Z. Studies also show a positive influence on vision including: improved visual acuity and visual processing speed, enhanced contrast sensitivity and speed of glare recovery. These two eye nutrients are great for everyone’s eyes, young and old, in order to improve visual performance and ocular health through better nutrition.