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  • - WELCOME TO THE SECOND SECTION ON VITAMINS.

  • THIS SECTION'S GOING TO BE COVERING VITAMIN D. WE'RE GOING

  • TO START WITH THE FUNCTIONS OR THE ROLES OF VITAMIN D.

  • AND THE MAIN FUNCTIONS ARE REGULATION OF BLOOD CALCIUM.

  • OUR BODY KEEPS CALCIUM

  • WITHIN THE BLOODSTREAM AT A VERY TIGHT LEVEL.

  • AND WHAT VITAMIN D IS IT HELPS REGULATE IT,

  • BUT MOSTLY WE THINK OF IT AS HELPING IN THE ABSORPTION

  • OF CALCIUM FROM THE INTESTINES INTO THE BLOODSTREAM.

  • ALSO HELPS US REGULATION OF PHOSPHORUS AND,

  • AND I JUST MENTIONED, RAISING BLOOD CALCIUM LEVELS,

  • DOING THIS BY INCREASING THE ABSORPTION.

  • THE MAIN CONDITION

  • IN VITAMIN D DEFICIENCY HAPPENS IN CHILDREN.

  • AND IT'S A SOFTENING OF BONES.

  • AND YOU CAN SEE IN THIS IMAGE HERE HOW THE LEGS ARE--

  • THESE BONES ARE BONY.

  • THEY'RE NOT FRACTURING OR BREAKING, THEY'RE SOFTENING.

  • THEY'RE SO SOFT THEY CAN'T HOLD THE SUPPORT,

  • THE WEIGHT OF THE PERSON,

  • IN THIS CASE A CHILD THAT'S TO BE SUPPORT.

  • SO THIS IS A SOFTENING OF THE BONES AND IT'S CALLED RICKETS.

  • THIS OCCURS IN CHILDREN.

  • MOSTLY IT'S GOING TO OCCUR IN CHILDREN

  • DO NOT RECEIVE ANY SUNLIGHT.

  • SO THEY'RE GOING TO BE IN THE VERY,

  • VERY NORTHERN AREAS IN SAY ALASKA OR

  • SOME OF THE SCANDINAVIAN COUNTRIES.

  • AND THEY CAN BE SUSCEPTIBLE TO RICKETS.

  • IN ADULTS THIS CONDITION IS CALLED OSTEOMALACIA,

  • BUT IT'S NOT NEARLY AS COMMON.

  • SO RICKETS IS GOING TO BE IN CHILDREN,

  • OSTEOMALACIA IN ADULTS.

  • ONE THING I WANT TO POINT OUT IS IN RECENT YEARS--

  • MEAN IT STARTED DECADES AGO BUT IN THE MORE

  • RECENT YEARS AS WE COME MORE WELL KNOWN

  • AND MORE MAINSTREAMED THAT VITAMIN HAS MANY,

  • MANY MORE ROLES THAN JUST CALCIUM REGULATION.

  • AND THESE ARE JUST A PARTIAL LIST,

  • AN INCOMPLETE LIST OF ALL THE CONDITIONS THAT

  • A VITAMIN D DEFICIENCY OR INSUFFICIENCY MAYBE

  • IS NOT TOO SEVERE THAT CAN RESULT IN.

  • SO CARDIOVASCULAR DISEASE, CANCER,

  • COGNITIVE DISORDERS, ASTHMA, DIABETES,

  • MULTIPLE SCLEROSIS, HYPERTENSION,

  • JUST A PARTIAL LIST.

  • AND ONE OF THE REASONS IS THAT VITAMIN D WILL BIND

  • TO SMALL AREAS OF DNA AND IT INITIATES THIS CASCADE

  • MOLECULAR INTERACTIONS, AND THIS IMPACTS GENES.

  • AND OF COURSE GENES DRIVE EVERYTHING AND

  • THEY'VE FOUND OUT THAT ARE MORE THAN 50 GENES

  • AND TISSUES THROUGHOUT THE BODY THAT ARE KNOWN TO BE

  • REGULATED BY THE ACTIVE FORM OF VITAMIN D. IN ADDITION,

  • VITAMIN D HAS A ROLE INTO WHICH THE DEGREE

  • IN WHICH CELLS WILL ACTUALLY CHANGE FROM

  • A LESS SPECIFIC CELLS TO MORE SPECIFIC CELLS.

  • AND WHAT I MEAN IS THERE CAN BE A GENERALIZE CELL THAT COULD

  • HAVE ANY NUMBER OF FUNCTIONS BUT WHAT'S CALLED DIFFERENTIATION,

  • AND YOU DON'T NEED TO KNOW THAT TERM,

  • BUT YOU SHOULD KNOW THAT IT REALLY HELPS IN THAT SPECIFICITY

  • OR THAT ONE GENERAL CELL BECOMING A VERY SPECIFIC CELL.

  • AND THAT'S VERY IMPORTANT FOR ALL CELLS THROUGHOUT THE BODY.

  • VITAMIN D TOXICITY IS NOT AS

  • COMMON AS WE USED TO THINK IT WAS,

  • AS I MENTIONED IN THE LAST LECTURE.

  • BUT IT STILL CAN OCCUR, AND I'LL ACTUALLY GET INTO IT

  • WHEN WE START TALKING ABOUT VITAMIN K THAT HOW THESE

  • TWO VITAMINS INTERACT AND CAN RESULT IN SOME OF THE TOXICITY

  • THAT WE SEE WITH VITAMIN D. WHAT IT USUALLY RESULTS IN IF

  • YOU THINK ABOUT THE FUNCTION OF VITAMIN D WHICH IS TO--

  • I MEAN IT REGULATES BLOOD CALCIUM BUT IT

  • REALLY ENHANCES THE ABSORPTION OF CALCIUM

  • FROM THE INTESTINES INTO THE BLOODSTREAM,

  • JUST BRINGING CALCIUM INTO THE BLOODSTREAM.

  • BUT IF YOU HAVE TOO MUCH VITAMIN D

  • THEN YOU CAN GET TOO MUCH CALCIUM.

  • IN ADDITION, IT'S NOT GOING TO

  • NECESSARILY BE IN THE RIGHT SPOT.

  • AND WE'D LOVE TO HAVE MORE CALCIUM IN THE BONES, RIGHT.

  • WELL, IF YOU GET TOO MUCH CALCIUM AND IT DOESN'T KNOW

  • WHERE TO GO IT'S GOING TO DEPOSIT IN OTHER AREAS,

  • USUALLY IT'S SOFT TISSUE CALCIFICATION.

  • HERE THIS IS A BONE, AND THIS IS A BONE HERE,

  • THIS IS IN THE SHOULDER, THE HUMERUS, AND THE CLAVICLE.

  • WHEN WE LOOK INTO THE TENDON AREAS OR WITHIN

  • THE LIGAMENTS YOU CAN GET THESE CALCIFICATIONS,

  • CALCIUM ACTUALLY DEPOSITING IN THOSE AREAS.

  • NOW, THIS IS JUST AN ARTERY HERE AND CALCIUM CAN DEPOSIT

  • IN THE ARTERIES THAT CONTRIBUTES TO SOMETHING

  • CALLED ARTERIOSCLEROSIS, WHICH WE'LL LEARN ABOUT.

  • AND THEN IN THE HEART, SO THIS IS AORTIC STENOSIS.

  • YOU DON'T NEED TO KNOW THAT TERM BUT IN THE HEART,

  • THE VALVES IN THE HEART CAN BECOME CALCIFIED,

  • AND THERE ARE NOT [INAUDIBLE] FUNCTION AS PROPERLY.

  • SO THESE ARE THE PROBLEMS THAT COULD

  • HAPPEN WITH VITAMIN D TOXICITY.

  • BUT DO KEEP IN MIND THAT IT'S NOT THAT COMMON AND

  • VITAMIN A TOXICITY IS ACTUALLY MORE COMMON JUST BECAUSE OF

  • THE FORTIFICATION AND SUPPLEMENTATION COMBINATION.

  • IT ALL RHYMES FOR SOME STRANGE REASON.

  • SO WHERE DO WE GET VITAMIN D?

  • WELL, SUNSHINE IS THE BEST SOURCE.

  • THE PROBLEM IS THAT MOST PEOPLE LIVE IN AN AREA WHERE YOU'RE

  • NOT GOING TO GET ENOUGH SUN NO MATTER HOW MUCH YOU'RE OUTSIDE.

  • DOESN'T MATTER IF YOU'RE RUNNING NECKED ALL DAY,

  • YOU ARE NOT GOING TO GET ENOUGH

  • SUN JUST BECAUSE OF THE SUN ANGLE.

  • SO IF YOU LIVE IN FLORIDA,

  • YOU LIVE IN THE BAHAMAS, YOU'RE ON THE CARIBBEAN,

  • LIVE IN SOUTHERN CALIFORNIA YOU HAVE A CHANCE OF GETTING

  • ENOUGH VITAMIN D. IF YOU LIVE IN HUMBOLDT COUNTY YOUR CHANCES

  • OF GETTING VITAMIN D FROM THE SUN ARE REALLY SMALL.

  • IN ADDITION TO THE SUN ANGLE,

  • ESPECIALLY DURING THE WINTER MONTHS,

  • YOU ALSO HAVE TO FIGHT WITH FOG, RIGHT.

  • AND IN SOME AREAS, SAY IN L.A.,

  • THEY MIGHT HAVE SO MUCH SMOG

  • THAT IT ACTUALLY CAN BE A PROBLEM.

  • BUT THE GENERAL RULE OF SAYING ABOUT 15-20 MINUTES

  • OUTSIDE PER DAY ON AVERAGE ESPECIALLY IN THE SUMMER

  • IN USUALLY IN THE 10:00-2:00 RANGE,

  • MAYBE 10:00-4:00 IN SHORTS AND T-SHIRT.

  • NOW, OF COURSE YOU'RE NOT GOING TO DO THAT IN MANY PLACES,

  • LET'S SAY BOSTON OR CHICAGO IN THE WINTER TIME,

  • AND EVEN THEN THE SUN ANGLE'S TOO LOW.

  • SO IN THAT CASE YOU REALLY HAVE TO GET IT FROM FOOD SOURCES

  • WHICH IS DIFFICULT OR YOU MAY ACTUALLY HAVE TO SUPPLEMENT.

  • AND REMEMBER I HAVE BEEN A VERY STRONG

  • ADVOCATE OF GETTING ALL OF YOUR VITAMIN MINERAL,

  • VITAMIN NUTRIENTS, ALL OF YOUR NUTRIENTS FROM FOOD.

  • THIS IS ONE CASE THAT IF VITAMIN D DEFICIENCY

  • AND INSUFFICIENCY HAS BECOME VERY COMMON,

  • AND YOU MIGHT GET SOMETHING YOU HAVE TO SUPPLEMENT.

  • NOW, WHAT ARE THE FOOD SOURCES?

  • COULD YOU GET IT FROM FOOD?

  • WELL, YEAH, SEAFOOD SALMON IS A GOOD SOURCE.

  • NOT EVERYONE HAS ACCESS TO FISH OR CAN AFFORD FISH,

  • YOU KNOW, A FEW TIMES A WEEK.

  • FORTIFIED MILK,

  • SO WE HAVE VITAMIN A AND D ARE USUALLY FORTIFIED IN MILK.

  • SO THAT'S WHERE A LOT OF PEOPLE GET THEIR VITAMIN D. EGG YOLK

  • IS ALSO A SOURCE OF VITAMIN D. AND THEN A RADIATED MUSHROOM,

  • AND THAT SOUNDS HORRIBLE.

  • WHAT'S IN IT THAT RADIATED?

  • BUT REALLY THEY'RE PUTTING MUSHROOMS AND THEY GET UV LIGHT,

  • AND SO THEY'RE PRODUCING THEIR OWN FORM OF VITAMIN D. IT'S

  • SLIGHTLY DIFFERENT FROM THE FORM WE HAVE BUT WE CAN CONVERT IT.

  • INDEED THERE ARE SOME FOOD SOURCES,

  • AGAIN, NOT A LOT OF OPTIONS.

  • THERE AREN'T A LOT OF OPTIONS OUT THERE SO

  • IT'S VERY DIFFICULT TO GET VITAMIN D FROM FOOD.

  • IF YOU'RE LIVING IN THE RIGHT AREA YOU CAN EASILY

  • GET ENOUGH VITAMIN D FROM THE SUN AND FROM FOOD.

  • BUT KEEP IN MIND IN HUMBOLDT COUNTY

  • IT'S UNLIKELY YOU'LL GET ENOUGH.

  • I DON'T RECOMMEND JUST SUPPLEMENTING.

  • I WOULD RECOMMEND TALKING TO YOUR

  • DOCTOR ABOUT A VITAMIN D TEST FIRST.

  • THEN YOU ONLY WANT TO SUPPLEMENT WHEN THERE'S DEFICIENCY.

  • AND THIS IS A SHORT VIDEO BUT THIS IS

  • THE END OF THE SECTION ON VITAMIN D.

  •  

- WELCOME TO THE SECOND SECTION ON VITAMINS.

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B1 中級 美國腔

9.2 維生素:維生素D (9.2 Vitamins: Vitamin D)

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    wenwen 發佈於 2021 年 01 月 14 日
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