What are the connections between caffeine, coffee and eye health? Do the negatives outweigh the positives? This is a tricky question, given the contradictory research on this popular beverage. Coffee is high in antioxidants that have broad health benefits. However, coffee is typically acidic, which can cause stomach symptoms. The caffeine in coffee is a stimulant that increases alertness, but it can also cause energy crashes. Caffeine research has not yet pinpointed the ideal amount of caffeine for better health. According to Traditional Chinese Medicine, coffee can be helpful or harmful, depending on the constitution of the drinker.
For coffee lovers, you will be happy to know that coffee is high in antioxidants, and provides a number of positive benefits if taken in moderate amounts. Keep reading to find out how coffee can be both beneficial and detrimental. Also, we reveal a study about a link between instant coffee and eye health – specifically, macular degeneration.
Pros and Cons of Caffeine
Caffeine is a stimulant found in plants, including cocoa beans, coffee beans, and black and green tea. Smaller amounts of caffeine intake have been found to have potential health benefits, e.g. coffee contains antioxidant phenols and reduces the risk of developing neurodegenerative disease and other health conditions, including Type 2 Diabetes Mellitus and liver disease. Studies are mixed, but some studies show that small amounts of caffeine are healthy.
At the same time, on the negative side, coffee can increase serum homocysteine and cholesterol levels and therefore has adverse effects on the cardiovascular system.1 According to another study, three cups or more of caffeinated coffee per day was associated with higher risk of developing exfoliation glaucoma.2 This type of glaucoma is caused by the buildup of a flaky, protein-like material, and it is the most common type of secondary open-angle glaucoma. Recent studies indicate that consuming three to four cups of coffee daily (equivalent to 300–400 mg of caffeine) poses minimal health risks and may even offer certain health benefits.3 These benefits were associated with a lower risk of developing cardiovascular disease, coronary heart disease, and stroke compared to individuals who do not consume coffee.4
The potential health benefits and risks of coffee consumption for both eye health and overall wellness can vary based on individual factors, such as a person’s unique constitution and their living environment. For people living in a cold environment, hot coffee can be very warming. For those living in a hot environment, it may create too much heat.
Traditional Chinese Medicine (TCM), Coffee and Eye Health
From a Traditional Chinese Medical perspective, excessive amounts of coffee will agitate the liver yang. Symptoms can include headaches (typically on one side of the head or in or above the eyes), breaking blood vessels on the outside of the eyes (sclera), elevated eye pressure (IOP), red eyes, visual disturbances, ocular migraines, possible changes in eyesight, ringing in the ears, dizziness, dry mouth, heavy feeling, insomnia, and increases in blood pressure. Too much coffee can stimulate internal wind with symptoms that can include the following: pain that moves around, itchy skin conditions, dizziness/vertigo, tremor or spasms, suddenly appearing rashes, sudden onset of headache or migraine with vertigo, or possibly sudden onset of disease.
People who are yang deficient (low in energy and generally cold overall) may find moderate amounts of coffee therapeutic to warm the body and stimulate yang. Excessive amounts can eventually have the opposite effect by depleting the adrenals.
Coffee is warm, sweet, and bitter. The slight sweetness of coffee also makes it mildly tonifying and nourishing. The primary bitter taste has the action of drying and dispersing. It can also clear heat, which helps balance out the very warm nature of coffee. Coffee moves Qi and Blood in the large intestine, which may reduce the risk of colon cancer, according to TCM.
Coffee Provides Warmth and Heat
In traditional Chinese medicine, food is divided into five natures: cold, cool, neutral, warm, and hot. Coffee brings warmth and heat to the body. So, a person who tends to have too much heat should avoid coffee or keep it at a minimum. Common symptoms of chronic heat include feeling hot, sweating all the time, being grumpy, having a swollen tongue, and often being constipated.
Coffee can be helpful for those who tend to be cold and/or damp. Common symptoms of having a cold constitution include being pale, having cold hands and feet, sensitivity to cold temperatures, feeling weak, and having poor circulation. Dampness tendencies include being overweight, particularly around the stomach, distended stomach, sticky mouth, greasy tongue, swelling, water retention, loose stool, and/or nodule masses (lymph nodes).
Suggestion: Limit yourself to one cup of coffee, tea, or cocoa daily. Best served unsweetened.
Macular Degeneration (AMD), Instant Coffee and Eye Health
A study found that drinking instant coffee may raise the risk of developing dry age-related macular degeneration (AMD). Experts believe the risk may come from harmful compounds such as acrylamide and oxidized fats that form during the high-heat processing of instant coffee. These substances may damage the retina over time.
While the study doesn’t prove instant coffee directly causes AMD, researchers say the findings are worth considering.5
Healthy Coffee Alternatives
Mushroom-based “Coffee Replacements”
Found easily online, mushroom coffee drink powders are made from functional mushrooms like lion’s mane, chaga, reishi, cordyceps, and turkey tail. These blends are designed to provide an energy boost and mental clarity similar to coffee. And, most have little to no caffeine. Serve hot or cold with sweetener. Check the label, because some have small amounts of coffee in the mix.
Green and Black Tea, and Decaf
This popular teas contain high amounts of catechins, which are antioxidants that can reduce the risk of cardiovascular disease, improve brain health, and potentially aid in weight management.
- A cup of green tea has about 29mg of caffeine, 1/3rd the amount of caffeine in coffee
- A cup of black tea has about 47mg of caffeine, 1/2 the amount of caffeine in coffee
- Matcha, a type of powdered green tea, can have caffeine levels comparable to coffee.
- A cup of decaffeinated coffee has between 2 mg and 14 mg of caffeine. Decaffeinated versions of green and black tea are also available.
*Coffee has approximately 94 mg of caffeine – sometimes more. Caffeine content varies widely, depending on how it is grown, processed and brewed.
Low-Acid Coffee
Some coffee lovers are deterred by the pain of acid reflux. Coffee is acidic. Also, caffeine speeds the metabolism, which can increase stomach acid production. Fine blends of low-acid coffee are available online.
Size matters: Note that the big cups at coffee shops and restaurants can hold far more than 1 cup of coffee or tea. Check their website for estimated caffeine content.
Why Green Tea is Good For You
Even though cocoa has more catechins per gram, green tea is more famous as a source. Through studies with lab animals, researchers have found that green tea catechins are passed from the digestive system into the tissue of the eye.6 Green tea contains a variety of phytonutrients that make it a very inexpensive superfood costing pennies per cup.
The infusion of Matcha green tea leaves, in contrast to other types of infusions, has the highest amount of caffeine and L-theanine.7
Antioxidant Protection
Tea catechins protect against oxidative stress due to chemical damage; they also protect mitochondria.8 9 and act as an antioxidant to counter the harm due to alcohol.10
Diabetic Retinopathy
Green tea consumption appears to protect against complications of diabetes.11 12 13
Lowering blood pressure
Green tea’s catechins may improve blood pressure and help lower cholesterol.
Dry Eyes
The catechins of green tea are effective in treating dry eye and meibomian gland dysfunction.14 These glands secrete oily meibum on top of the tear film to slow evaporation. The catechins of green tea regulate and reduce symptoms of autoimmune imbalances, as is exhibited in Sjogren’s syndrome.15 16
Herbs That Boost Energy
Herbs that naturally boost energy and promote a healthy immune system include: Ashwagandha, Schishandra, bilberry, Lycii Berries, Astragalus, Pasax quinquefolius (American Ginseng), and Zingiber officinale (Ginger).
Suggested Supplements
Advanced Eye & Vision Support Formula (whole food)
Dr. Grossman’s Meso Plus Retinal Support and Computer Eye Strain Formula with Astaxanthin
Dr. Grossman’s Advanced Eye and Dr. G’s Whole Food Superfood Multi1 20 Vcap Combo – 2 months supply
ReVision Formula (wild-crafted herbal formula) – based on classic Chinese medicine Liver tonic formula to help support healthy circulation and blood flow throughout the eyes and body.
Dr. Grossman’s Tired Eyes and Fatigue Formula
Dr. Grossman’s Bilberry/Ginkgo Combination
H2 Elite Molecular Hydrogen 60 tabs
NMN Wonderfeel Capsul 60 vegcaps
Recommended Books
Natural Eye Care: Your Guide to Healthy Vision and Healing
Natural Parkinson’s Support: Your Guide to Preventing and Managing Parkinson’s
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