Green Smoothie Bliss

(Was Popeye Secretly on Dialysis?)

Thomas Lodi, MD, MD(H)

Green Smoothie Bliss


There has been some confusion being expressed on the Internet regarding the oxalate content in green smoothies along with a ‘dire warning’ (in at least one article) to avoid drinking liquid sunshine.

This sort of confusing rhetoric (spin-propaganda) is intended to bewilder and baffle people rather than to enlighten them and is always to be expected whenever a true healing modality directly from the loving hands of nature (and non-patentable) gains in popularity. And, although I appreciate the compassionate tone of these commentaries to help mitigate the occurrence of calcium-oxalate kidney stones, what is glaringly absent from these admonitions are warnings for people to avoid or at least reduce their intake of animal protein and refined carbohydrates, which for the population at large, should be of much greater concern than green smoothies.

Four types of kidney stones?

Four major types of kidney stones can form:

  • Calcium stones are the most common and occur in two major forms: calcium phosphate and calcium oxalate.
  • Uric acid stones result when the urine is consistently acidic. Eating purine rich food (animal protein) can result in calcium urate stones (or uric acid stones).
  • Struvite stones are associated with kidney infections.
  • Cystine stones are a consequence of a specific genetic disorder.

Oxalates in Human Food

Other than cocoa, coffee and chocolate, there are many foods commonly found in the human diet that contain oxalates in significant concentrations including:

  • Fruits
    • mafuang (star fruit or carabola),berries, currants, kiwifruit, concord (purple) grapes, figs, plums, and tangerines.
  • Vegetables
    • Parsley, beet greens and roots, spinach, Swiss chard, collard greens, okra, leeks, celery, and rutabagas.
  • Seeds and Nuts
    • Pumpkin, squash, sunflower, and poppy seeds, quinoa   (a seed) almonds, cashews, macadamia, filberts, etc.
  • Legumes
    • Soybeans (tofu) and peanuts
  • Grains
    • Wheat bran, wheat germ, buckwheat
  • Other
    • Cocoa, chocolate, green and black tea

Note: leaves contain higher concentrations of oxalates than do stems, stalks and roots.

What are oxalates?

Oxalates are the salts of oxalic acid, which occur naturally in many plants as a product of metabolism.  

Salts (‘ions’/charged) result from neutralizing acids and consist of positively charged ‘cations’ in association with negatively charged ‘anions’ in a solution, such as water.  There needs to be a certain amount of water (solute) to keep the salt in its’ ionic form. Below a certain threshold amount of water, the ‘cations’ and ‘anions’ come together (precipitate) to form crystals, e.g., table salt.

Oxalates are divalent anions, which means they can “grab” two monovalent cations like two atoms of potassium OR one divalent cation, like calcium, iron, magnesium, etc.





When ingested oxalates that are not bound by cations in the gut   (e.g., calcium) can be absorbed directly into the blood and travel to the kidneys, where if the conditions are suitable and there is sufficient calcium present, calcium-oxalate crystals form. Whether the oxalate and calcium remain in ionic form or crystalize (precipitate) depends upon several factors including pH (acidity), water content (hydration status) and the presence of other nutrients.

The point at which precipitation (crystallization) occurs is known as the saturation point and is dependent upon a multitude of factors other than the oxalate content of food. *

In fact, the oxalate content of food actually has little relevance as to whether or not oxalate stones will form in the kidneys.

There are multiple studies on rats AND humans indicating that high dietary intake of calcium actually reduces the incidence of oxalate kidney stones and furthermore, that magnesium and potassium intake are inversely related to oxalate stone formation.  

Hence, the more calcium, magnesium and potassium that are in the diet, the more the ingested oxalates will be bound (in the intestines) and thereby excreted through the bowels rather than be reabsorbed into the blood and subsequently excreted through the kidneys, where they could precipitate to form crystals (stones).  Additionally, the presence of adequate magnesium in the blood greatly reduces the likelihood of calcium-oxalate stone formation, as well.

* The solubility (dissolvability) of oxalates varies greatly depending upon the cations present.  The most soluble (dissolvable) are magnesium (Mg) and calcium (Ca) and the least soluble are the ‘heavy metals’ like lead (Pb) and mercury (Hg).  Therefore, when oxalates are bound to magnesium or calcium, they are more likely to remain dissolved and not crystalize, whereas when bound to ‘heavy metals’, like lead or mercury, they crystalize quite readily.

Dietary vs. Supplemental Calcium

A very important distinction needs to be emphasized between true dietary minerals (e.g., calcium) vs. supplemental calcium in pill or powder form. It has been shown that although high intake of dietary calcium decreases the risk of kidney stones, the intake of supplemental calcium can actually increase the risk of stone formation depending upon timing and amount.


The metabolic pathway outlined above represents the endogenous production (made by the body) of oxalates and clearly shows that kidney stones are related to dietary protein and refined carbohydrates, not to the oxalate content of food.  

Furthermore, some foods that have quite high oxalate contents like black and green tea actually appear to be preventative with regards to oxalate stone formation.

A very interesting study published in 1998 in the Annals of Internal Medicine evaluated just over 81,000 women from ages 40 to 86 years who had no history of kidney stones. The results were quite confusing to these researchers since for each cup of green tea consumed on a daily basis, the women’s risk of kidney stones was actually reduced by 8 percent. In another study involving men, it was found that for each cup of tea consumed, their risk of kidney stones was reduced by 14 percent.

How Important are Dietary Oxalates?

It is well known that 80-90% of oxalates excreted in the urine are endogenously produced (made in the body) thereby decreasing the potential role of dietary oxalates to between 10-20%.  

Since dietary oxalate intake accounts for such a small amount of the oxalates actually found in the urine of people who form calcium oxalate stones, it is now fairly well accepted that dietary restriction of oxalate containing foods is not a viable therapeutic intervention to prevent stone formation, except in a few rare circumstances, hypercalciuria type II and hyperoxaluria (primary and enteric).

However, even in conditions involving fat malabsorption or inflammatory bowel disease (enteric hyperoxaluria), if probiotics are taken daily for 2 months, the saturation of the urine is reduced to such an extent that approximately 25% less calcium related (oxalate) stones are formed.

When any of these conditions do exist however, the recommendation is that only about ¼ cup of spinach or its’ equivalent should be consumed per day.  That still ‘leaves’ plenty for many smoothie recipes.

What Causes Kidney Stones

Recent research indicates that the intake of refined carbohydrates, protein, calcium, and water are much more relevant to calcium oxalate stone formation than dietary oxalates.

The British Association of Urological Surgeons published the following, which is in full agreement by the international medical community in all medical specialties: “Dietary advice to increase the consumption of fibre and reduce the consumption of sugar, refined carbohydrates and animal protein produced a significant reduction in the urinary excretion of calcium, oxalate and uric acid.”

Animal Protein

Animal based diets generate large amounts of acid in the various fluid departments of the body hence, the kidneys respond by excreting all excess acids to maintain an alkaline pH in the blood and ECM (fluid bathing the cells).

Calcium, in the form of calcium bicarbonate (Ca(HCO3)2, calcium carbonate (CaCO3) and calcium phosphate (CaPO4) is released from the bones (in order to neutralize the excess acid) where it enters the blood, the extra cellular fluid (ECM) and through the kidneys, thereby increasing the amount of urinary calcium available to precipitate with oxalates to form stones.  This homeostatic response by the body to maintain functional integrity however results in a net calcium loss from the bones (osteoporosis).

In other words, calcium is leached from the bones to neutralize the acids formed by consuming animal protein resulting in super saturation of calcium in the urine available for stone formation AND less calcium in the bones (osteoporosis).

Additionally, animal protein is the major dietary source of purines, which are broken down into uric acid that leads to uric acid kidney stones and excruciatingly painful crystals in joints (Gout).  

Of great import, it should be noted that dietary vegetable protein consumed in high amounts does not contribute to these same pathological changes in uric acid metabolism and calcium metabolism, hence does not lead to Gout, osteoporosis, kidney stones or kidney failure, as does large amounts of animal protein.

“A study conducted in the UK showed that a diet low in animal protein reduced the prevalence (occurrence) of urinary stone formation by 40-60%”. (see references)

“A high animal protein intake causes a significant increase in the urinary excretion of calcium, oxalate, and uric acid, 3 of the 6 main urinary risk factors for calcium stone formation. (see references)

“High amounts of dietary protein can lead to increases in both calcium and oxalate levels in the urine. The elevated protein results in lower urine pH — an acidic environment that makes it easier for calcium oxalate kidney stones to form. It also decreases citrate levels in the urine that help prevent kidney stones from forming. ….”      (see references)

Refined “Naked” Carbohydrates

Refined carbohydrates are fruits, vegetables, legumes or grains that have been stripped of most nutrients except the simple sugar. Nature does not produce isolated, simple carbohydrates (sugars),) but rather produces complexes, which include all macronutrients (e.g., proteins & fats), enzymes, vitamins and cofactors in sufficient quantities required to metabolize the natural, complex carbohydrates in that particular plant appropriately.  There is no excess of these “cofactors” in plants so that when carbohydrates are isolated (stripped) from their accompanying nutrients, the body must “borrow” the necessary cofactors in order to metabolize these “naked carbohydrate”.

Of note: Cooking vegetables, fruits and grains is one method of turning a wholesome food into a ‘refined carbohydrate’; cooked vs. raw carrots is an example.


Hypercalciuria (excess calcium in the urine) is thought to be partially mediated through the insulin / glucagon pathways, which are required to metabolize carbohydrates and can result in hyper saturation of urinary calcium with a concomitant increase in calcium-oxalate stone formation (as well as calcium urate and calcium phosphate). Calcium-oxalate stone formation is specifically increased in individuals with an abnormal insulin response.

Other variable that mediates calcium saturability are magnesium, potassium and water.


Refined carbohydrates, (e.g., sucrose) disturb magnesium balance in the body by depleting magnesium levels in the metabolic requirements necessary to process simple sugars. Magnesium is required for ATP (energy) formation .  Magnesium is essential for stimulating hormonal and enzymatic responses to put calcium into the bones and out of the blood and urine (kidneys). Another one of magnesium’s many functions is to keep calcium in solution, which prevents it from crystalizing….hence, even when dehydrated, if there is sufficient magnesium, calcium will stay in solution. Finally, magnesium directly binds to oxalate in the gut allowing it pass through without being reabsorbed.

If there is not enough magnesium to keep calcium in solution, various forms of calcification will occur from stones, muscle spasms, fibrositis, fibromyalgia, and atherosclerosis (calcified plaques in the arteries).  In fact, magnesium has been used effectively to prevent recurrent kidney stones.


Every green plant derives its’ color from chlorophyll, the molecule that transforms sunlight into biologically available energy, ATP.  Even those plants that are not green have chlorophyll that is being masked by higher concentration of anthocyanins (red/purple) or carotinoids  (yellow/orange), which are the other two pigments found in plants.

Chlorophyll is chemically a porphyrin ring, just like the ‘heme’ in our hemoglobin (blood).  But, unlike our blood, which has iron in the center, the chlorophyll molecule has magnesium in the center of every porphyrin ring.  

Clearly then, every plant, green and otherwise (including spinach) has abundant magnesium AND calcium AND potassium. In fact, this combination of minerals certainly contributes to the universal finding that vegetarians have significantly less kidney stones (including calcium oxalate) than humans who have “derailed” and gone astray down the omnivore path; eating diets not dissimilar from their canine friends who are certainly much further away on the phylogenetic tree than their close cousins, the tailless primates who refrain from such indiscriminate scavenging.

“Vegetarian diets are associated with low excretion of calcium, oxalate, and uric acid and may lower the risk for urolithiasis in a number of ways. These include the absence of animal protein and provision of higher amounts of magnesium and potassium, both of which are associated with lower risk for stone formation.” (see references)


All of these substances in the blood are contained in the ‘water’ portion of the blood.  Water, keep in mind is the “universal solvent”. As the proportion of water increases, crystals “disappear” and then reappear when the relative amount of water decreases.  In biological system, this is referred to as “hydration” and “dehydration” As the Mayo Clinic advises, “Not drinking enough water each day can increase your risk of kidney stones. People who live in warm climates and those who sweat a lot may be at higher risk than others.”

Another one of the numerous benefits of eating uncooked (raw) vegetables and fruits is that they have not had the water removed via the cooking process.  Even when cooked with water, such as boiling or steaming, it is the water within the cells of the food (plant or animal) that is removed, thus removing the milieu necessary for life.  

So, in a soup where all the ingredients are “drowning” in water, it is the ‘intracellular water’ that has been removed by the heating process and along with it, the ‘life force’, or electromagnetic tension that defines life.

This is the reason that people are not thirsty after eating fruit or a purely vegetable salad.  The food is completely hydrated, hence the hydration status of the eater is not changed. Dehydrated food, through the law of osmosis (thermodynamics), extracts water from the body to satisfy this non-negotiable law of nature and hence the body’s homeostatic mechanisms elicit ‘thirst’ to compensate for the water loss.

So, God’s Wearing a White Coat These Days?

The European Molecular Biology Organization, in 2011 published an article, Molecular Breeding of Healthy Vegetables to provide a rationale for why science is in the process of usurping God’s (nature’s) role.  

The purpose of the article was to “discusses recent attempts to characterize and modify phytochemicals in vegetable crops by using molecular approaches, focusing on those modifications that are of interest to consumers.”

The article explains how scientists are attempting to “hide” what they have determined as important and eliminate what they have determined is unnecessary in fruit, vegetables and nuts (seeds).

This way food producers can “attempt to break into the US$18 billion snack-food industry”, like they did in 2010 with “creation” of ‘baby carrots’.  

Greed and outrageous arrogance is easily concealed under the pretense of beneficence whose rhetoric hypnotizes the gullible with words such as, “about 3 billion people in the world are malnourished due to imbalanced diets. Vegetables can contribute to the prevention of malnutrition disorders. Genetic engineering enables vegetable breeders to incorporate desired transgenes into elite cultivars, thereby improving their value considerably.” (see references)

These plant breeders and scientists have determined that certain foods contain ‘anti-nutrients’ defined as, “naturally occurring compounds with inhibitory effects on the nutritive potential of plants.”  The goal then is to reduce certain nutrients and increase others according to their understanding of nature..

Nature is incomprehensibly complex hence altering one aspect will only induce the biological imperative to maintain homeostasis and purpose.  Even the scientists recognize this, “specific function of calcium oxalate accumulation in plants is not known; it might have a role in calcium regulation, ion balance, plant protection, detoxification or light gathering.”  Nevertheless, since 1994, there have been attempts to lower the oxalate content of certain vegetables.

Molecular biology labs around the world have been highly involved with the “molecular cloning of oxalate decarboxylase gene to remove nutritional stress (oxalic acid) from plants” since the 1990s.

Dire Warning:

Whether or not articles on the internet are meant to obfuscate and overwhelm the reader with disinformation or are merely a product of naïve ignorance or are driven by ego requirements, it is imperative at this time in human history that we maintain a vigilant stance to protect our biology and hence, life on planet earth.

Clinical Experience

Over the past 10 years, we have designed and supervised over 1000 green juice ‘feasts’ where people mostly with advanced stages of cancer (some early stages) would stop eating solid food and drink 3 to 5 quarts per day of freshly prepared juice for a duration of 1 to 4 weeks.  

Although the juice recipe was adjusted occasionally for individual taste, each was a slight variation of our primary recipe of spinach, kale, celery, cucumber, green apple and lemon.

After the ‘feast’, these people transitioned into a raw, vegan diet, which included green smoothies each morning. They are given the knowledge and tools to continue this dietary regimen after leaving the center and are followed closely for approximately 9 to 12 months after which they modify their diets to include 20 to 30% cooked, vegan food.  This modified 80:20 / 70:30 regimen ALWAYS includes daily green smoothies and green juice along with a diet of abundant unprocessed fresh vegetables, fruits and nuts.

During this 10-year period, we have had ZERO incidences of calcium oxalate or calcium urate stones.  Furthermore, I began this program five years prior in New York, where again, we had ZERO incidences of calcium oxalate crystal formation in the kidneys of our patients.  

The experience at our center is not unique.  There are five well-known centers in the US (and many lesser known) providing the same services AND countless others in Canada, Europe, Australia and New Zealand.  Furthermore, we are seeing this awakening occur in Singapore, Malaysia, Philippines, Thailand, Hong Kong and China.


May I refer the reader to an easy to locate video, which follows two very unhealthy, obese men for 60 days of juice ‘feasting’                 (and the sequel), Fat, Sick and Nearly Dead (1 & 2).           

Again, no stones!


Unless one has hypercalciuria type II and hyperoxaluria (primary and enteric), there is no reason to avoid healthy foods that contain natural oxalates found in plants.  And, in fact the research actually corroborates our clinical findings (over 15 years) that drinking green juices and smoothies are not only health promoting in multitudinous ways, but are actually protective against the development of kidney stones, both calcium-oxalate and urate varieties.

The vast majority (80-90%) of oxalates found within the body are produced endogenously (from within) in the liver as an aspect of glycolate (carbohydrate) metabolism.

Precipitation of oxalates to form calcium-oxalate crystals (coalesce into ‘stones’) only occurs under very specific conditions related to hydration (water) status, pH of the urine, and the concentration of calcium, magnesium and potassium.

The biochemical milieu in the blood and kidneys that favor stone formation is directly correlated to the intake of refined carbohydrates and animal protein AND inversely correlated with amount of natural sources of calcium, magnesium and potassium (fresh green vegetables, fruit, and seeds/nuts).

Happily, then:

Our staff and patients (>1000 people) have remained oxalate and uric acid stone free over 15 years by drinking a minimum of 1 to 2 quarts per day of fresh green vegetable juice, enjoying a green smoothie, and eating abundantly of the green leafy vegetables, fruits and nuts/seeds that are, for the most part, prepared without employing the destructive force of fire (not cooked).

This daily dietary regimen is augmented 3 to 4 times per year with green juice ‘feasts’ for on an average of 10 to 14 days.


We don’t have a lot of biographical information regarding Popeye, however looking at his images, one can see that he was thin, energetic, affable, strong and considering his competence in battle, apparently quite healthy.

Furthermore, there were no dialysis catheters inserted into his bare arms in all of the images ever produced of our spinach obsessed hero, who may have been a vegetarian, for all we know.

  1. Wellington Wimpy, (“Wimpy”), on the other hand ate substantial amounts of animal protein and refined carbohydrates with apparently little, or no vegetables (spinach).  

Furthermore, he always wore a long sleeve coat, perhaps to conceal his dialysis catheters…one can only speculate.        

   Green Smoothie Bliss


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This Road to Health Hell is Paved with Toxic Oxalate Crystals

The Green Smoothie Fad:

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