Should I listen to my wife? And Why Do You Still Take a Multi, or Do You?
I often get questions about what is in our bestseller books (Yes, I am proud of 4 #1 NY Times Bestsellers)—the RealAge and the YOU series , like YOU: Staying Young!  So I am answering one that represents a common thread.  And I apologize for being more scientific (with the references) rather than just action steps and making the physiology (why it works) fun as in the books.   Here is the question (you can always send me questions at youdocs@gmail.com).
Q1) I’m confused—one headline reads vitamins are so useless you should throw em out, and another that they prevent cancer in old guys like me.  I’m 76 and retired, and spend much time that I enjoy with my wife.  She has one bad habit (or maybe it’s good)—she reminds me to take my meds and then watches me take ‘em (I suppose I should be happy she cares that much). She now wants me to take a multi a day like she does.   Can I tell her NO?  Name withheld by request, from Lyndhurst, Ohio. 
 
A1: I’m sorry; She’s right, if she’s recommending you take a multi daily and not mega doses of any one vitamin or mineral. If you only cared about preventing cardiovascular disease (heart attacks, strokes, impotence, skin wrinkling, kidney failure) the jury was still out till recently.  But now there is substantial evidence of benefit for long term multi use for reducing the risk of those illnesses, as well as cancer. 
Yes, the data were clear fifteen or more years ago for the benefit for preventing cancer (18% prevention for all men over age 70, and greater benefit for preventing recurrences, even in men who are physically active and eat well), or you were of potentially pregnant age (men and women) as it is clear that they decrease the risk of autism and autism spectrum disorders by about 40% (if taken for three months prior to by both man and woman, and thru  pregnancy for a woman), childhood cancers to age 6 (by 65 percent) and neural tube defects (like spina bifida) by over 80%. 
But let’s focus on you and cardiovascular disease since that’s the newest data. Now before I go on, know that I am prejudiced, as I chaired the scientific advisory board of a company that produces DHA Omega-3 whose parent is a leading vitamin supplier.
What is the New Data on A Multi a day for 20 years (and by the way this comes from the same research group housed at Harvard that previously had reported no benefit in the first 10 years). (reference #1)  In this longer term report of the outcome of 18,530 male physicians with over 20 years of records, those that took a multivitamin a day for over 20 years had a significant and large 44% lower risk of heart attacks or strokes, and a 14% lower risk of needing cardiac revascularization (stents and/or cardiac surgery) (reference#2).  No change was found in the first 10 years of these men who were on average under 50 years of age at the start of the data collection, as reported in an earlier study by the same group (reference #1). This process is not unexpected as most heart attacks and strokes occur after age 60; it takes events happening to be able to prevent events. So in this long term study in initially healthy men, multivitamin use for over 20 years was associated with a big reduction of major cardiovascular disease. 
Now let me tell you why (since I didn’t know those study results till they were recently revealed and published) I’ve been taking half a multi morning and night since I reviewed the data for the RealAge.com program in 1994.
The data then in the literature and since were and have continued to be strong enough to convince me that some vitamin supplements including a daily multi (in small doses to insure against an insufficient diet), and some other nutritional supplements, have plenty of health-protecting benefits -- especially if you’re over 50, munch a less-than-perfect diet, are a woman of reproductive age, or are among the tens of millions (reference #3)  of Americans who take nutrient-zapping drugs for high blood pressure, diabetes, or to tame stomach acid. When you add it all up…that’s a lot of folks. So why the opposition to multivites?
One meta-study conducted for the U.S. Preventive Services Task Force looked at 27 supplement studies involving more than 400,000 people. (reference#4) It found no benefit for longevity, cancer prevention, or heart health in people without nutrient deficiencies.  The second followed 5,947 guys for 12 years and found that multivitamins didn’t sharpen thinking or memory in men who ate healthy diets. (reference #5)
The third tracked more than 1,700 heart-attack survivors for a very short time, and, again, found no heart-health benefits for those who took a multivitamin, but plenty of people dropped out of that study. All three studies appeared in the same issue of the Annals of Internal Medicine. (reference #6)  An editorial writer told readers “Enough is Enough: Stop Wasting Money on Vitamin and Mineral Supplements”.
I have a different message for our readers. I want you to know that these studies really found that if you eat well almost all the time or only take your vitamins some of the time, you won’t get a benefit in the first 10 years at age 50 in heart disease prevention. But clearly the data show, both in cancer and cardiovascular and stroke prevention, that the older you are, and the longer you take that multi, the greater and more substantial the benefit. And the benefits—18% for cancer prevention at age 70, (reference #7) and 44% for cardiovascular disease prevention (reference #2) in exercising healthy eaters where the benefit should be less than in people with the average American diet or who don not exercise regularly—are substantial. 
The studies also showed no harm from taking multivitamins. Those data in favor of a multi in preventing cancer and CV disease are why do I still recommend most people take a half a daily multivitamin containing important nutrients at levels close to their recommended daily allowance twice a day. No mega-vitamins, please!  And men and postmenopausal women should look for one without iron.
Here's the full list of benefits.
If you’re over age 50, like our questioner is: A multivit can reduce risk for non-prostate cancers in men by 6 to 18% (reference #7) and cut risk for adenomas -- polyps that can become colon cancers -- by 20%. (reference #8) To cut your risk for vision loss and early forms of age-related macular degeneration, add 900 mg of DHA and a lutein and zeaxanthin supplement (like I do); these help guard your eyes.
If you take a diuretic, an acid-blocking proton pump inhibitor (PPI), or the diabetes drug metformin: Some diuretics can reduce your body’s stores of potassium and magnesium, needed for healthy muscle function and great blood pressure. PPIs, can lower levels of B12, (reference #9) a vitamin that helps your body make red blood cells, nerves and DNA. And metformin can reduce magnesium (reference #10) (important for healthy blood pressure) as well as B12. (reference #11) And many of you are iodine deficient as well if you are using iodine free sea salt.
Since more than 90% of those taking the nutrition test at RealAge.com (it is free) do not get recommended amounts of one or another vitamin or mineral in their diet, we think half a multi twice a day is a great inexpensive insurance policy against an imperfect diet Take enough magnesium, foliate, B12, B6, and Vitamin D3: Turn to brown rice, almonds, hazelnuts, spinach, shredded wheat, lima beans, and bananas to top off your tank (or, just get ½ a multi-mineral and multi-vitamin supplement twice a day—that decreases your cardiovascular risks by 44% and your cancer risks by 18% if taken for 20 years through age 70 according to the Health Professional’s Studies).  (references #1 and #2).
If you think a 44% reduction in heart attacks and strokes and a 18% reduction in cancer rates is worth it when you hit age 70, then you should too, questioning guy from Lyndhurst.  And certainly all women who are potentially possibly going to be pregnant should.
The reason to split your multivitamin down the middle, and take half in the morning and half at night? You'll urinate out soluble vitamins in 12 to 16 hours, so this split will keep the level in your body steady. (reference 12) In addition, I take a daily DHA omega-3 supplement (900mg –I  am over 60 and my tabs have lutein and zeaxantin, too);  vitamin D-3 (2,000 IU), and suggest up to 600 milligrams of supplemental calcium. In a future column we may get the chance to review the rest of the Fab 8 supplements I think should be routine.
Thanks for reading. Feel free to send questions—to youdocs@gmail.com, and some of them we may know enough to answer (we’ll try to get answers for you if we do not know).
REFERENCES:
1.  Sesso HD, Christen WG, Bubes V, Smith JP, MacFadyen J, Schvartz M, Manson JE, Glynn RJ, Buring JE, Gaziano JM. Multivitamins in the prevention of cardiovascular disease in men: the Physicians Health Study II randomized controlled trial. JAMA 2012;308:1751–60.
2.  Rautiainen S, Rist PM, Glynn RJ, Buring JE, Gaziano JM, Sesso HD.  Multivitamin use and the risk of cardiovascular disease in men.  J Nutr 2016; 146:1235-40.
3. IMS Institute for Healthcare Informatics: "The Use of Medicines in the United States: Review of 2010," April 2011.
4. Fortmann SP, Burda BU, Senger CA, Lin JS, Whitlock EP. Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: an updated systematic evidence review for the U.S. Preventive Services Task Force. Ann Intern Med 2013; 159:824-34.
5. Grodstein F, O'Brien J, Kang JH, Dushkes R, Cook NR, Okereke O, et al. Long-term multivitamin supplementation and cognitive function in men. A randomized trial. Ann Intern Med 2013; 159:806-14.
6. Lamas GA, Boineau R, Goertz C, Mark DB, Rosenberg Y, Stylianou M, et al, TACT (Trial to Assess Chelation Therapy) Investigators. Oral high-dose multivitamins and minerals after myocardial infarction. A randomized trial. Ann Intern Med 2013; 159:797-804
7. Gazino JM, Sesso HD, Christen WG, et al.  Multivitamins in the prevention of cancer in men.  JAMA 2012; 308(18):1871-1880.
8. Massa J, Cho E, Orav EJ, Willett WC, Wu K, Giovannucci EL. Long-term use of multivitamins and risk of colorectal adenoma in women. Br J Cancer 2014 Jan 7;110(1):249-55. doi: 10.1038/bjc.2013.664. Epub 2013 Nov 12 http://www.ncbi.nlm.nih.gov/pubmed/24220696
9.  http://jama.jamanetwork.com/article.aspx?articleid=1788456
10.  http://www.plosone.org/article/info:doi/10.1371/journal.pone.0074355
11. http://www.diabetes.org/news-research/research/access-diabetes-research/long-term-metformin-use-may-1.html
12. http://health.clevelandclinic.org/2012/05/multivitamins-insurance-against-an-imperfect-diet/