MCS Consensus III Postscript Splash: Micronutrients - Vegetables Essential

[michael edward badolato jr]

MCS Consensus III Postscript Splash: Micronutrients - Vegetables Essential

Vitamins, Minerals, Phytoestrogens, Lignans, Flavonoids, Glucosinolates, more:

vegetables are primary in meeting the RDA for many essential nutrients;

provide potassium supporting lean muscle mass, activity level, strength, endurance;

the difference between 34 oz vegetables per day and 12 oz includes nutrient deficiencies and 45 mg/d increased urinary calcium loss, likely major to bone health. Vegetables and fruit are the only source of necessary alkalinity so that renal net acid excretion (RNAE) is not excessive;

nutrients and fiber for immuno-stimulation and detoxification;

antiviral, anticancer, and antioxidant properties;

promoting health; preventing disease.

An ongoing process, antioxidant reactivity results in toxic metabolites and phase II glutathione detox enzyme activity. Accompanied with overproduction of reactive species, oxidative stress occurs when toxic levels are not attenuated and metabolites are not readied for excretion promptly.

DRI 2006: "...oxidative stress...imbalance between the production of various reactive species and the ability of the organism's natural protective mechanisms to cope with these reactive compounds and prevent adverse effects..."

While there is no RDA for the vast majority, it is the broad presentation of whole food phytochemicals that taken together are protective, but cannot be expected to counter overwhelming oxidative input such as SJF (specified junk food) or polluted environment.

Phytoestrogen Lignans

Lignans including matairesinol (MAT), secoisolariciresinol (SECO), and their glycosides - are transformed by large intestinal bacteria to the mammalian lignans: enterolactones and enterodiols (Rodriguez-Garcia 2019, Wang 2002, Tham 1998).

RODRIGUEZ-GARCIA 2019: "...A beneficial inflammatory marker profile [lower C-reactive protein and white blood cell counts] is associated with adult lignan consumption (Eichholzer 2014)..." 

                         highest amounts   mg/100g

vegetables:      broccoli                     98          fruit:      pear           18

                                kale                            63                        apricot       11

                          brussels sprouts      50                        peach          7

                          green beans              23                        nectarines  5

                                white cabbage          21

                          green bell pepper     12     

                          cauliflower                  9

                          red bell pepper           8  

whole grain: lignans are found in the fiber outer layer of whole grain; little in the endosperm of a refined grain product.

Flavonoids  (Pennington 2005)

anthocyanidins: grapes and berries

flavan-3-ols: scattered among fruits, in a few vegetables

flavones: celery, parsley, thyme, peppers, queen anne's lace, little elsewhere

flavanones: citrus fruits

isoflavones; daidzein, genistein, glycitein: soybeans, soy products - soy is too oily

flavonols; isorhamnetin, kaempferol, myricetin, quercetin: fairly wide distribution; higher amounts in tea, cranberries, some types of green leafy such as kale, collard greens

mg/100g (3.5oz)    Isorhamnetin  Kaempferol  Quercetin   (Huang 2007)

    collard greens              -                   43                 12               

    kale                              23                  90                 32

Both at high concentration: quercetin, in countering hydrogen peroxide, protected DNA but formed thiol reactive quercetin metabolites leading to glutathione loss, impaired calcium sequestration, and cellular damage in vitro (Boots 2007). This study result is consistent with the suggestion that concentrating exposure to phytochemicals out of whole food matrix such as in supplements, extracts, juices, or cooking water, may not be a good idea.  Elevated hydrogen peroxide is usually involved with oxidative stress, and thiols refers to the cysteine thiol component of glutathione.

Boots A.W. et al.The quercetin paradox. Toxicol Appl Pharmacol 222;1:89-97 2007 

Eichholzer M. et al. Urinary lignans and inflammatory markers in the US National Nutrition Examination Survey (NHANES) 1999-2004, 2005-008, Cancer Causes Control 25;395-403 2014

Huang Z. et al. Phenolic compound profile of selected vegetables frequently consumed by African Americans in the southeast United States. Food Chem 103:1395-1402 2007 

Pennington J.A.T. & Douglass J.S. Bowes and Church's Food Values of Portions Commonly Used. Lippincott, Williams, and Wilkins 2005

Glucosinolates

Although alligator kale and mustard greens may not be edible, the latter perhaps due to high levels of sinigrin; and cooking seems necessary for all: generally the level of glucosinolates found in brassica vegetables is thought beneficial - these sulfur compounds referred to as protective factors. Brassica vegetable consumption, shown to be antioxidant and anticarcinogenic, may result in significantly less DNA damage even though pungent acrid isothiocyanates, noted in cabbage, are potentially toxic and mutagenic at high concentrations.

(Drewnowski 2000)                                   Food Source            Amount   

glucobrassicin                                          brussels sprouts     220-1100  mg/kg

progoitrin                                                  brussels sprouts     100-1000   "    "

                                                                   turnip or swede        90-830      "    "

                                                                                  cabbage                    10-80        "    "

                                                                   cauliflower                0-140        "    "

                                                                                  calabrese                   0-82           "    "       

sinigrin                                                      mustard greens    6930-7790 umol/kg  

                                                                   collard greens         625-1973    "     "

                                                                   brussels sprouts     110-1560   mg/kg

                                                                   cabbage                     70-410      "    "

                                                                   cauliflower                 10-630      "    "

                                                                   kale                              0-287    umol/kg

                                                                   turnip or swede          0-100     mg/kg

                                                                   broccoli                       0-16      umol/kg

                                                                   calabrese                     0-10       mg/kg

isothiocyanates

allyl-isothiocyanate                                  cabbage                     2-146      mg/kg
3-methyl-sulfinylpropyl isothiocyanate        "                            4-175        "   "
benzyl isothiocyanate                                     "                           1.2-75        "   "
4-methylsulfinyl butyl isothiocyanate           "                             0-75         "   "
phenylethyl isothiocyanate                            "                             3-75         "   "     

Vegetable Preparation

Blanching is placement in already boiling water or steam stopping enzyme action, followed by ice water bath and freezing: retaining color, flavor, texture, nutritive value; while removing dirt, bacteria, chemical residue; reducing glucosinolate/isothiocyanate related bitterness; and lowering flavonol levels. Frozen supermarket vegetables are blanched, thus cooked, although labels recommend further cooking which results in loss of nutrients.

Home Blanching   (Meyer 1970)    Freezer storage maximum: 0 degrees/F, 1 year; 5 degrees/F, 6 months   

Bring water to rapid boil, pot covered tightly with glass lid, add vegetables keep covered, blanching time begins when boiling has resumed. 

Boiling time (minutes), submerge in ice bath for equivalent period (placing vegetables in a mesh basket then submerging may work well). If steaming, stand greens up like trees and add 1 minute to the boiling time.

     broccoli                  sea level  2-4      5000 feet  3-5     

     brussels sprouts                    3-5                        4-6

     cabbage                                   2-3                        3-4

     cauliflower                               4-5                        5-6

     collard greens                           2                           3

     kale                                             1                           2

     turnip greens                             2                           3

If consuming immediately - remove hot vegetables promptly to a cool serving container, eat while still warm, and discard cooking water. The color should be green, flavorful not bitter, texture still somewhat crisp, wilted rather than excessively matted, though often will mat. May want to allow slightly longer cooking time for cabbage and collard greens.

There is a window of optimal flavor between overcook toward brownian; and undercooked bitterness. It is a quick steam or boiling hot process; not prolonged high temperature.

Alternative method for cooking (not blanching)   MCS 2021 Exclusive

Add 8-12 ounces water to a tall heat distributing copper or aluminum clad bottom stainless steel cooking pot and stand collards or kale upright like trees. Cover pot with glass lid and bring to boiling steam on medium heat (not so hot as to scorch) which may take about 8 minutes; after only a few additional minutes or less steaming, vegetables should be optimal: total time 8-15 minutes depending on heat setting, altitude, and ambient temperature. As above, remove promptly to a cool container, consume while still warm; and with respect to contaminant, glucosinolate/isothiocyanate, and flavonol levels: it may be good to discard cooking water.  

Drewnowski A. et al. Bitter taste, phytonutrients and the consumer: a review. Am J Cl Nutr 72:1424-35 2000

Meyer, Hazel. Complete Book of Home Freezing. J.B. Lippincott Co. 1970