Foods appear to be better carriers for probiotics than supplements, but if one chooses to go with the supplement route, should they be taken before, during, or after meals?
The package labeling on probiotic supplements is often confusing. Sometimes the consumer is instructed to take the probiotics with meals, sometimes before or after meals, and occasionally on an empty stomach. I was surprised to find so few actual data in the scientific literature concerning this topic, but that is par for the course for most dietary supplement advice. See, for example, my video series about how little pharmacists and natural food store employees know:
- Health Food Store Supplement Advice
- Bad Advice From Health Food Store Employees
- Dangerous Advice From Health Food Store Employees
- Pharmacists Versus Health Food Store Employees: Who Gives Better Advice?
The lack of information on how to take probiotics has led to serious confusion, both for the industry and the consumer. Surprisingly it doesn’t appear as if any studies had ever examined this question–until now.
Researchers hoped to be able to measure probiotic concentrations throughout the entire process after taking a probiotic supplement minute-by-minute. To do this, they had to build a fake digestive track with a fake stomach and intestines, but complete with real saliva and digestive enzymes, acid, bile, and other digestive fluids. What did they find? If you check out my 2-min video Should Probiotics Be Taken Before, During, or After Meals?, you can see the survival of three different types of probiotics before, during, and after meals. You can also see how the probiotics fared when taken in oatmeal and milk, milk alone, apple juice, or water.
What did they find? Like vitamin D supplements, which should also probably be taken with meals for maximum efficacy (Take Vitamin D Supplements With Meals), probiotic bacterial survival was best when provided within 30 minutes before or simultaneously with a meal or beverage that contained some fat content.
This study didn’t shed light on what dose we should take and under what circumstances, however. To see what the best available science says, see the first video in this series, Preventing and Treating Diarrhea with Probiotics. Then I compared probiotics to prebiotics in Preventing the Common Cold with Probiotics? and moved to the effect of your gut flora on your mood in Gut Feelings: Probiotics and Mental Health.
-Michael Greger, M.D.
Image credit: Eric C Bryan / Flickr
Babies delivered via caesarean section appear to be at increased risk for various allergic diseases. The thought is that vaginal delivery leads to the first colonization of the baby’s gut with maternal vaginal bacteria. C-section babies are deprived of this natural exposure and have been found to exhibit a different gut flora. This concept is supported by research noting that a disturbance in maternal vaginal flora during pregnancy may be associated with early asthma in their children. This all suggests our natural gut flora can affect the development of our immune system (for better or for worse).
In adulthood, two studies published back in 2001 suggested that probiotics could have systemic immunity-enhancing effects. Subjects given a probiotic regimen saw a significant boost in the ability of their white blood cells to chomp down on potential invaders. (You can watch a video of white blood cells doing their thing in my video Clinical Studies on Acai Berries. A must-see for biology geeks :). And even after the probiotics were stopped, there was still enhanced immune function a few weeks later compared to baseline (check out my 4-min video Preventing the Common Cold with Probiotics? to see the graph). A similar boost was found in the ability of their natural killer cells to kill cancer cells.
Improving immune cell function in a petri dish is nice, but does this actually translate into people having fewer infections? For that, we had to wait another 10 years, but now we have randomized double-blind placebo controlled studies showing that those taking probiotics may have significantly fewer colds, fewer sick days, and fewer symptoms. The latest review of the best studies to date found that probiotics, such as those in yogurt, soy yogurt, or supplements, may indeed reduce one’s risk of upper respiratory tract infection, but the totality of evidence is still considered weak, so it’s probably too early to make a blanket recommendation.
Unless one has suffered a major disruption of gut flora by antibiotics or an intestinal infection—in other words unless one is symptomatic with diarrhea or bloating—I would suggest focusing on feeding the good bacteria we already have, by eating so-called prebiotics, such as fiber. After all, as I noted in Preventing and Treating Diarrhea with Probiotics, who knows what you’re getting when you buy probiotics. They may not even be alive by the time we buy them. Then they have to survive the journey down to the large intestine (Should Probiotics Be Taken Before, During, or After Meals?). Altogether, this suggests that the advantages of prebiotics—found in plant foods—outweigh those of probiotics. And by eating raw fruits and vegetables we may be getting both! Fruits and vegetables are covered with millions of lactic acid bacteria, some of which are the same type used as probiotics. So when studies show eating more fruits and vegetables boosts immunity, prebiotics and probiotics may be playing a role.
How else might we reduce our risk of getting an upper respiratory infection? See:
- Can Gargling Prevent the Common Cold?
- Are Cats or Dogs More Protective For Children’s Health?
- Sleep & Immunity
- The Risks and Benefits of Neti Pot Nasal Irrigation
The immune boosting fruit and vegetable video I reference in Preventing the Common Cold with Probiotics? is Boosting Immunity Through Diet. See also Kale and the Immune System and the subject of my post last week, Boosting Immunity While Reducing Inflammation.
-Michael Greger, M.D.
Image credit: stevendepolo / Flickr