Sunday, February 23, 2014

IBD and the Americans With Disabilities Act

Is IBD a Disability?


This post is United States specific, but I would welcome comments from those in other countries about the applicable law in their location.  Here we look at the evidence for IBD as a disability.  In the case of the United States, evidence comes in the form of the law and of legal precedent.  The governing law in this case is the Americans with Disabilities Act (ADA). 

The ADA was passed in 1990, and the most relevant piece for those with IBD, Title 1, applies to employers and states that a covered entity shall not discriminate against a qualified individual with a disability, and requires covered entities to make reasonable accommodations that do not pose an undue burden for those with disabilities.  The other titles of the ADA deal with commercial facilities, public transportation, and similar entities.  While it does not directly address federal employees, they are covered under Section 501 of the Rehabilitation Act.(1)

A person with a disability is defined by the ADA as anyone who:

Has a physical or mental impairment that substantially limits one or more major life activities

Prior to 2008, the definition was narrow and likely did not cover Crohn’s Disease or Ulcerative Colitis.  In 2008, the Act was amended to include the following language:

[A] major life activity also includes the operation of a major bodily function, including but not limited to, functions of the immune system, normal cell growth, digestive, bowel, bladder, neurological, brain, respiratory, circulatory, endocrine, and reproductive functions(2)

The inclusion of “bowel” and ”digestive” functions as “major life functions” seemingly includes IBD sufferers as potentially covered.  There have been some cases that have addresses this in the courts:

·         In EEOC v. University of Maryland Faculty Physicians, Inc., an employee in the Pediatrics unit who answered phones and scheduled appointments, was terminated for missing work.  The employee, Doneen King, suffered from Crohn’s Disease and missed two weeks of work due to disease activity that resulted in 2 ER visits and one hospitalization.  King requested an additional day of unpaid leave, and was terminated for violation of the organizations Lateness and Attendance policy.  King was awarded $92,500 as a result of a settlement and under consent decree the organization was required to change its attendance policy to cover King as a reasonable accommodation.(3)
·         In EEOC v. Browning-Ferris, a boom truck driver with Crohn’s disease, Deborah Brown, was terminated by her employer.  They alleged that exposure to the waste management environment would exacerbate her condition and that the conditions may be “life threatening” for her.  As a result, they terminated her employment.  Under consent decree Brown was paid $194,000 and reinstated to her position.(4)
·         In Wingrad v. Pennsylvania State Police, a case that is currently ongoing, 911 was called to get medical assistance for the plantiff’s son.  The State Police arrived and found the son was agitated and mentally confused due to medication related to his depression and IBD.  The son took a swing at one of the police, and they Tasered him and restrained him in a way that caused cardiac arrest, and then failed to perform resuscitation.  The lawsuit alleges that the Pennsylvania State Police failed to appropriately train officers, pursuant to ADA, on dealing with individuals that have physical and mental disabilities.  While there are likely additional factors in this case that have not yet come to light, it will be interesting to watch in 2014.(5)

While lawsuits are the result of organizations NOT abiding by federal law, what are reasonable accommodations that can be made without causing things to escalate to that level?  This mostly applies to the workplace in practice, since that is where many of us spend the majority of our time.  First off, to avoid having any protracted battles it is recommended that you have your physician write a letter stating that you have active Crohn’s Disease or Ulcerative Colitis and that you require special accommodations – the CCFA provides a sample letter here.  The law only requires your employer to make accommodations that are reasonable – this would preclude actions like building a new bathroom just for you at a small store or letting you work from home when you occupy the position of a receptionist.  There are many accommodations that are reasonable, however, and these can include:

·         Starting work an hour later or earlier to avoid getting caught in traffic (with no access to a bathroom)
·         Taking your own vehicle on corporate field trips to avoid being stuck in a bus with no restroom
·         Being seated closer to the restroom
·         Being allowed to access restrooms in other areas
·         Having the ability to be flexible in scheduling sick leave
·         Taking more frequent breaks that are unscheduled
·         Being provided a private location to take medication

The specific accommodations requested will likely be tailored to your particular job situation.  There is nothing stopping you from being creative in working with your employer to find a mutually beneficial solution.

While non-employer accommodations are also required (allowing the use of an employee bathroom at a retail store could be reasonably argued as being required), this area of the law has not been well litigated with respect to IBD and arguing the finer points of the ADA isn’t likely to help in a crisis situation.  In states where Ally’s Law is in place, things are clearer.

Bottom Line


·         The Americans with Disabilities Act includes the digestive system as a major bodily function, making IBD a covered condition.
·         Those with IBD are entitled to reasonable accommodations – especially at their employer.


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Sunday, February 16, 2014

Sex and Inflammatory Bowel Disease

Sexual Desire, Satisfaction, and Ability with IBD


For those who have Crohn’s Disease and Ulcerative Colitis, where discussions of bowel movements have become comfortable and commonplace, sex can sometimes be a taboo subject.  There are implications on sexual function, both psychological and physiological, associated with IBD.  These are exacerbated by a fear of talking about them – both with partners and with care providers.  Additionally, physicians are frequently hesitant in asking about sexual function – furthering the taboo.  What are the implications of IBD on sexual health?

First, the psychological concerns have been looked at from a few different perspectives.  In a small survey-based study of 188 patients (with all of the limitations of survey self-reporting), subjects with IBD had no statistical difference when compared to controls in frequency of sexual intercourse, though the study used subgroup analysis that weakened the reliability of the results (188 patients – four subgroups for gender and type of IBD, each subgroup was approximately 44 patients).  The study did should that there were primary concerns in the IBD group about fecal incontinence, urgency, and abdominal pain, however.(1)  Other studies have shown an impact psychologically based on disease severity, with female patients having more concerns about intimacy.(2)  A larger European study of approximately 3,000 patients should a marked impact on sexual function in a quality of life questionnaire.  While having the same self-reporting related issues, the controls in this study appear to have been stronger.  This study showed a significant quality of life difference related to sexual activity in those with IBD, but did not attempt to qualify the reasons behind it.  Of interest in this study, the quality of sexual activity was inversely correlated with frequency of disease symptoms – those with more severe disease had the highest impact on sexual activity.(3)  Studies looking at ileostomy patients have shown an even more marked concern for sexual performance, attractiveness, and related issues.(4)

In the largest physiological study related to IBD and male sexual function, there were strong correlations between disease activity and erectile dysfunction (OR 2.5, CI 1.3-4.9), ability to have an orgasm (OR 4.3, CI 2.0-9.3) and sexual desire (OR 2.5 CI 1.1-5.5).  Interestingly, all of these factors were directly related to the severity of the disease (as expected) but inversely related to the duration of the disease.  This suggests that individuals who have the disease for longer periods are more likely to have found help for their conditions or adapted to them better.(5)

In a counterpart study, the same group from (5) looked at female sexual function.  They found that women reported having lower sexual desire (OR 1.8 CI 1.0-3.2) associated with active disease, and increases vaginal infection rates.  Similar to men, having IBD for more than 10 years correlated with more positive sexual health and activity.(6)

For patients that have anal involvement in their Crohn’s and Ulcerative Colitis, there is a relationship between anal damage and the ability to achieve erection in men.  This was found to be a problem with men having anal fistula surgery, specifically in those with incontinence issues.  The role of anal function in erection is related to the nerves that are present in the area.  Perianal involvement and subsequent damage through fistulotomy can negatively impact those nerves (http://en.wikipedia.org/wiki/File:Pudendal_nerve.svg), resulting in ED issues.(7)

Bottom Line


·         Sexual desire and function are impacted negatively by Crohn’s and Ulcerative Colitis, through physiological and psychological means.
·         The psychological sexual impact tends to be less for those who have had IBD for more than 10 years.  An exact reason for this is not known.
·         Perianal involvement can have high ED association for men due to the location of the nerves involved in penile muscle stimulation.
------------------------------------------------------------------------------------------------------------------------------
1.       Moody, G. A., and J. F. Mayberry. "Perceived sexual dysfunction amongst patients with inflammatory bowel disease." Digestion 54, no. 4 (1993): 256-260.
2.       Drossman, Douglas A., Jane Leserman, Z. M. Li, C. Madeline Mitchell, E. A. Zagami, and DONALD L. Patrick. "The rating form of IBD patient concerns: a new measure of health status." Psychosomatic Medicine 53, no. 6 (1991): 701-712.
3.       Haapamäki, J. 2011. Health-related quality of life, symptoms and comorbitity in inflammatory bowel disease. Medical dissertation, University of Helsinki.
4.       Carlsson, E., I. Bosaeus, and S. Nordgren. "What concerns subjects with inflammatory bowel disease and an ileostomy?." (2009).
5.       Timmer, Antje, Alexandra Bauer, Daniela Kemptner, Alois Fürst, and Gerhard Rogler. "Determinants of male sexual function in inflammatory bowel disease: A surveybased crosssectional analysis in 280 men." Inflammatory bowel diseases 13, no. 10 (2007): 1236-1243.
6.       Timmer, Antje, Daniela Kemptner, Alexandra Bauer, Angela Takses, Claudia Ott, and Alois Fürst. "Determinants of female sexual function in inflammatory bowel disease: a survey based cross-sectional analysis." BMC gastroenterology8, no. 1 (2008): 45.
7.       Shafik, A. "Injured external anal sphincter in erectile dysfunction." Andrologia33, no. 1 (2001): 35-41.

Sunday, February 9, 2014

Scientific and Pseudoscientific Terminology

Theories, Hypotheses, Opinions, and Beliefs

The purveyors of pseudoscience frequently use linguistic gymnastics to give their claims an air of legitimacy.  The technical differences in terms used interchangeably in common parlance may be irrelevant to anyone not looking to pick a pedantic fight.  Unfortunately, they can be intentionally misused to equate to very different concepts and put them on the same level – cheapening one and unfairly validating the other.  Depending on how they are used, those seeking to educate may take different approaches.

The misuse isn’t always intentional – I’ve heard terms repeated by well-meaning individuals who generally don’t understand the scientific method.  Statements like “Well, it’s your belief that homeopathy won’t cure my Crohn’s and it’s my belief that it will, so it’s just as likely that I’m right” are hard to combat because they show the speaker lacks any grounding in how science works in general.  Attacking belief with fact is not likely to be fruitful without laying the groundwork.  Because the individual has a strong stance on homeopathy, you are better off trying to explain the scientific method in another area where they have neutral beliefs before talking about homeopathy treating IBD. 

If a person is well educated and has perhaps a blind spot for a particular area of snake oil (let’s call it the Pauling effect), a different approach may be necessary.  The person may say something like “I’ve got a PhD in astrophysics and I’ve read the facts differently than you and it is my opinion that the cosmic ray theory of Crohn’s Disease is correct*”.  In that case, the person is applying an opinion that they are allowing to override evidence, calling something a theory that may only exist in their head, and probably only reading information that supports their already formed beliefs (an example of confirmation bias).  Because the individual understands the scientific method, there may be a better way of confronting them.  Instead of providing counterarguments, it may be more fruitful to ask them questions about their belief that provoke self-reflection – “I’m interested in cosmic rays.  How do they relate to x-rays?  Would x-ray radiation also cause Crohn’s disease, then?  Are people who fly frequently more likely to get Crohn’s disease?  What about astronauts?”  Additionally, listen to their answers – if they have solid, new evidence to support their assertion, then it bears consideration. 

The final misuse category is intentional, and is used by individuals where they have little or no evidence to back up their claims and they know it so they create a false parity as substitute.  This can be the mark of a snake oil salesman (or just plain ignorance), but usually goes something like this “It is your theory that treating inflammation with Western medicine like the biological drugs helps out with IBD.  My theory is that acupuncture is a valid treatment for IBD.  We both will just have to agree to disagree on who is right.  What I will say, though, is that acupuncture doesn’t have the side effects that the biologicals do and it is a lot cheaper.”  While sounding magnanimous, this individual is taking a practice that has no grounding in the current understanding of anatomy, and equating it to the application of a treatment that is evidence based and supported through double blind trials repeated by independent researchers.  Additionally, they have applied a straw man approach – they have moved the discussion from whether or not acupuncture is effective to one where they are comparing the side effects (many placebo treatments have no direct side effects, only the harm caused by inaction – see http://whatstheharm.net/ for cases where “harmless” treatments have had less than desirable results).  Folks making these claims are not likely to be educated – you may be better off educating individuals that are making use of their “services”.

What is the difference between the terms in the title of this post?

Let’s deal with hypothesis first.  A scientific hypothesis is sometimes equated to a guess, which is inaccurate.  A hypothesis starts with observations and a theory of action that is grounded in science.  Based on the observations, a precise statement is made that is testable.  The method to forming a hypothesis might be something like the following:

1.       A doctor observes numerous IBD patients in her practice.  It appears, through observation, that many of the patients are suffering from anemia.
2.       Previous studies have shown that blood loss from other conditions can cause anemia.  The doctor has observed increased blood loss in the patients that have been anemic.
3.       The doctor hypothesizes that blood loss due to IBD causes a higher incidence of anemia amongst those with IBD.

For a hypothesis to be valid, it needs to be testable and falsifiable.  If it is not testable, there is no way to provide evidence to confirm the hypothesis.  It must also be falsifiable – capable of being proven false.  A hypothesis like “The magic of prayer causes intestinal healing, but getting tested to show the level of inflammation indicates a lack of faith, preventing the healing.”  While the statement may sound off the wall to anyone reading this blog, there is a large portion of the population that would not find it so.  Unfortunately, the statement does not qualify as a hypothesis because it is inherently non-testable (how do we measure “prayer”?) and non-falsifiable (any attempts to disprove the power will be self-referentially the cause of the failure).

A hypothesis leads to testing – hypotheses are not “proven”, they are tested or evaluated.  When testing, evidence and not “proof” is gathered.  In fact, a good scientist will seek to design studies that would invalidate their hypothesis if the evidence does not support it.  In medicine, placebo controlled double blind studies with large, representative samples have best track record in testing hypotheses without introducing bias.

A scientific theory is an explanation that starts out as a hypothesis, and undergoes rigorous testing.  Throughout the testing, the evidence is objectively weighed against the original hypothesis.  If, after extensive testing including independent confirmation all of the evidence supports the hypothesis, then it becomes an accepted theory.  Theories provide a tested explanation based on what the evidence shows.  There is no element of belief or opinion present.  Additionally, a valid theory is based on tests that can be replicated by anyone using a valid protocol.  Theories do not need to explain every aspect of a situation, and there can be competing theories that are supported by evidence.  When competing theories are present, it is generally because the current state of the science hasn’t adequately identified enough evidence to disprove one of them.  Theories can and do evolve as better testing methods and more rigorous applications of the scientific method become available (as opposed to dogmatic beliefs, which leave no room for change).  Once a scientific consensus has been reached (note: a consensus is a general agreement between the majority of educated practitioners in an area based on the supporting evidence for a theory – it does not require unanimity nor does it take the Family Feud approach by allowing for a theory to be a popularity contest not backed by evidence).

Opinions and beliefs have nothing to do with theories.  Theories are accepted, not believed (belief is a “trust, faith, or confidence in someone or something” – note there is no requirement for rationality, reason, or evidence).  A lawyer I knew once said “The two statements that have no place in the law are ‘I believe that…’ and ‘I feel that…’”.  The same holds true for science.

Although they are similar, opinions are beliefs that are backed up by evidence.  The evidence may be subjective, incomplete, or erroneously interpreted.  They may also be based on hard evidence.  Unfortunately, because opinions can be based on solid grounding, weak grounding, or even completely irrational grounding, they are more difficult to pin down.  An expert opinion can be as precise as a physician opining that an individual has Crohn’s disease due to the presence of intestinal inflammation, granuloma formation, and symptoms consistent with the disease with the lack of other proximate cause.  Unfortunately, many individuals are of the opinion that they have various diseases without going through any rigorous testing protocol “It’s my opinion that I have a gluten allergy because the day after I ate that large pizza my stomach was upset”.   Opinions, unlike beliefs, tend to be easier to form and easier to un-form.  A good physician is always willing to reconsider or revise a medical opinion as new evidence becomes available.

Bottom Line


·         While a philosophy lecture is more likely to discuss the uses of the terms hypothesis, theory, opinion and belief, their misuse can sow confusion for patients about what is and is not science-based medicine.
·         Practitioners and patients should be cautious about their own use (and misuse) of the terms, whether intentional or accidental.

* I’m unaware of any cosmic ray theory of IBD, though the intestines are particularly susceptible to radiation.  That fact alone, though, doesn’t even make the concept a complete hypothesis, let alone a theory.

Sunday, February 2, 2014

Vitamins and IBD - Other Common Deficiencies

Vitamin and Mineral Deficiencies and IBD


The previous two posts dealt with the general deficiencies that occur with IBD and dietary supplementation of iron.  This post deals with the other deficiencies and what nutritional supplementation may help.  Unlike iron, most of the vitamins and minerals noted below are only necessary in trace amounts. Those amounts may be higher with those suffering from Crohn’s Disease and Ulcerative Colitis, but are still on the low side.  Most of the impacted absorption involves B complex vitamins.  The US RDI* for the various vitamins and minerals are listed below ((the numbers are regularly tweaked):

Vitamin/Mineral
USRDI (in mg unless noted)
Thiamine (B1)
1.2
Niacin (B3)
16
Vitamin B6
1.3
Biotin (B7)
30 micrograms
Folate (B9)
400 micrograms
Vitamin B12
2.4 micrograms
Vitamin A
900 micrograms
Vitamin C
90
Copper
900 micrograms
Magnesium
400
Selenium
55 micrograms
Zinc
11
(1)

Being deficient in the various areas above can have different symptoms.  Depending on the time and amount of deficiency, they can range from a minor nuisance to severe.  Similarly, high doses of each can lead to toxicity.  A useful discussion of everything from Beriberi (thiamin deficiency) to scurvy (vitamin C deficiency) to hypozincemia (zinc deficiency) is the subject of a different post.  This one is about good sources of the vitamins and minerals.  The table below lists some food sources and their RDI percentage:

Vitamin
Sources

















Thiamine (B1)
Food
Bread
Cereals
















% RDI
17.1
11.8















Niacin (B3)
Food
Poultry
Bread
Cereals















% RDI
10.8
10.7
10.9














Vitamin B6
Food
Chickpeas, canned, 1 cup
Beef liver, pan fried, 3 ounces
Tuna, yellowfin, fresh, cooked, 3 ounces
Salmon, sockeye, cooked, 3 ounces
Chicken breast, roasted, 3 ounces
Breakfast cereals, fortified with 25% of the DV for vitamin B6
Potatoes, boiled, 1 cup
Turkey, meat only, roasted, 3 ounces
Banana, 1 medium
Marinara (spaghetti) sauce, ready to serve, 1 cup








% RDI
55
45
45
30
25
25
20
20
20
20







Biotin (B7)
Food
Brewer's yeast - dried
Chicken liver, fried
Kidney, fried
Egg, raw














% RDI
667
283
140
83













Folate (B9)
Food
Beef liver, braised, 3 ounces
Spinach, boiled, ½ cup
Black-eyed peas (cowpeas), boiled, ½ cup
Breakfast cereals, fortified with 25% of the DV†
Rice, white, medium-grain, cooked, ½ cup†
Asparagus, boiled, 4 spears
Spaghetti, cooked, enriched, ½ cup†
Brussels sprouts, frozen, boiled, ½ cup










% RDI
54
33
26
25
23
22
21
20









Vitamin B12
Food
Clams, cooked, 3 ounces
Liver, beef, cooked, 3 ounces
Breakfast cereals, fortified with 100% of the DV for vitamin B12, 1 serving
Trout, rainbow, wild, cooked, 3 ounces
Salmon, sockeye, cooked, 3 ounces
Trout, rainbow, farmed, cooked, 3 ounces
Tuna fish, light, canned in water, 3 ounces
Cheeseburger, double patty and bun, 1 sandwich
Haddock, cooked, 3 ounces
Breakfast cereals, fortified with 25% of the DV for vitamin B12, 1 serving
Beef, top sirloin, broiled, 3 ounces







% RDI
1,402
1,178
100
90
80
58
42
35
30
25
23






Vitamin A
Food
Sweet potato, baked in skin, 1 whole
Beef liver, pan fried, 3 ounces
Spinach, frozen, boiled, ½ cup
Carrots, raw, ½ cup
Pumpkin pie, commercially prepared, 1 piece
Cantaloupe, raw, ½ cup
Peppers, sweet, red, raw, ½ cup
Mangos, raw, 1 whole
Black-eyed peas (cowpeas), boiled, 1 cup
Apricots, dried, sulfured, 10 halves
Broccoli, boiled, ½ cup
Ice cream, French vanilla, soft serve, 1 cup






% RDI
1,403
6,582
573
459
488
135
117
112
66
63
60
278





Vitamin C
Food
561
444
229
184
249
54
47
45
26
25
24
20
Cantaloupe, ½ cup
Cabbage, cooked, ½ cup
Cauliflower, raw, ½ cup
Potato, baked, 1 medium
Tomato, raw, 1 medium

% RDI
158
155
117
117
107
100
85
82
80
65
65
55
48
47
43
28
28
Copper
Food
Legumes
Potato and potato products
Nuts and seeds
Beef
Pasta and pasta dishes
Ready-to-eat and hot cereals
Rice
Breads
Ground beef
Chocolate desserts
Fruit juices
Poultry
Fish
Dark green and deep yellow vegetables




% RDI
30
22
17
16
16
15
14
13
13
12
11
11
11
10



Magnesium
Food
Almonds, dry roasted, 1 ounce
Spinach, boiled, ½ cup
Cashews, dry roasted, 1 ounce
Peanuts, oil roasted, ¼ cup
Cereal, shredded wheat, 2 large biscuits
Soymilk, plain or vanilla, 1 cup
Black beans, cooked, ½ cup
Edamame, shelled, cooked, ½ cup
Peanut butter, smooth, 2 tablespoons
Bread, whole wheat, 2 slices
Avocado, cubed, 1 cup
Potato, baked with skin, 3.5 ounces
Rice, brown, cooked, ½ cup
Yogurt, plain, low fat, 8 ounces
Breakfast cereals, fortified with 10% of the DV for magnesium



% RDI
20
20
19
16
15
15
15
13
12
12
15
11
11
11
10


Selenium
Food
Brazil nuts, 1 ounce (6–8 nuts)
Tuna, yellowfin, cooked, dry heat, 3 ounces
Halibut, cooked, dry heat, 3 ounces
Sardines, canned in oil, drained solids with bone, 3 ounces
Ham, roasted, 3 ounces
Shrimp, canned, 3 ounces
Macaroni, enriched, cooked, 1 cup
Beef steak, bottom round, roasted, 3 ounces
Turkey, boneless, roasted, 3 ounces
Beef liver, pan fried, 3 ounces
Chicken, light meat, roasted, 3 ounces
Cottage cheese, 1% milkfat, 1 cup
Rice, brown, long-grain, cooked, 1 cup
Beef, ground, 25% fat, broiled, 3 ounces
Egg, hard-boiled, 1 large
Puffed wheat ready-to-eat cereal, fortified, 1 cup


% RDI
777
131
67
64
60
57
53
47
44
40
31
29
27
26
21
21

Zinc
Food
Oysters, cooked, breaded and fried, 3 ounces
Beef chuck roast, braised, 3 ounces
Crab, Alaska king, cooked, 3 ounces
Beef patty, broiled, 3 ounces
Breakfast cereal, fortified with 25% of the DV for zinc, ¾ cup serving
Lobster, cooked, 3 ounces












% RDI
493
47
43
35
25
23











Legumes
Potato and potato products
Nuts and seeds
Beef
Pasta and pasta dishes
Ready-to-eat and hot cereals
Rice
Breads
Ground beef
Chocolate desserts
Fruit juices
Poultry
Fish
Dark green and deep yellow vegetables





30
22
17
16
16
15
14
13
13
12
11
11
11
10





 (2-5)

The numbers above are not quite as simple as they appear.  Some minerals, like zinc, are excreted in different amounts by the kidneys based on intake.  Others, like Vitamin A, tend to accumulate in the liver to toxic levels if taken in on an erratic basis.  This is yet another reason to consult a Registered Dietician when doing your dietary planning – the complexities involved are fairly high.

One way that individuals with IBD can track their nutrition intake more accurately is with software (which doubles as a food diary, if symptoms are recorded).  LifeHack reviewed the major vendors, and recommended MyFitnessPal as a top choice.  They recommend four other programs as well – check out their reviews to see which may fit your platform best: http://lifehacker.com/five-best-food-and-nutrition-tracking-tools-1084103754.

Bottom Line


·         Nutrient levels are non-linear with consumption
·         Getting all of the right nutrients is difficult – having Crohn’s or Ulcerative Colitis-specific deficiencies makes it more difficult
·         Registered dieticians or software may help for tracking purposes

* The US Reference Daily Intake (RDI) is the Daily Value (DV) that is needed to ensure 99% of the population has an adequate amount of a vitamin and/or mineral.  This system replaced the old Recommended Daily Allowance (RDA) number.  The actual RDI is even more complicated as there aren’t daily allowances calculated for everything and other measures are used as substitutes.  The actual DV needed varies by sex, pregnancy status, age, and weight.  For IBD, it also varies by impact to absorption.

1.       -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------http://iom.edu/Activities/Nutrition/SummaryDRIs/~/media/Files/Activity%20Files/Nutrition/DRIs/RDA%20and%20AIs_Vitamin%20and%20Elements.pdf