Sometimes, figuring out what is healthy is confusing. The media seems to report something, then scientists come along and contradict it practically the next week. For example, eggs. Eggs used to be good, a great source of protein. Then eggs were bad, too high in cholesterol. Now eggs are good again, a great source of protein and what do you know, dietary cholesterol doesn't affect our blood cholesterol as much as we used to think (its really trans fat and high sugar that increase blood cholesterol).
Recently, supplements have been in the category of "contradictory and confusing topics". Some studies show they are good, while others show they are not so good. Often, it's just that new technologies are more sophisticated and discount older research. Sometimes news can be confusing because it's not apples-to-apples comparisons with each story. For example, fiber lowers cholesterol in people with high blood cholesterol but not in people with lower cholesterol. A journalist might not know that so they may blast a story that fiber doesn't work in their publication and ignore the fact that the subjects had perfectly healthy cholesterol to begin with. And other time, a food or supplement may be beneficial for one thing but not another.
For example, a recent paper just summed up the research on calcium and vitamin D supplements as follows: "the treatment of 1000 women with calcium plus vitamin D for 5 y would prevent 5 breast cancers and 1 colorectal cancer, and might prevent 1 fracture and 2 deaths, but would cause 4 myocardial infarctions [heart attacks] or strokes".
Um, not so much, right? But this seems to be how many things net out in nutrition. Take alcohol for example...1-2 glasses a day can reduce risk for having a heart attack, but it also increase risk for cancer (including breast cancer for women). It's almost like you're damned if you do, and damned if you don't.
My interpretation of this is a little bit different. For one, this shows me that we need to do more research to understand what is going on. What about vitamin D alone...does that show the same thing? What about if the calcium and vitamin D came from food instead of a supplement, would we see the same thing? And if its true that calcium and/or vitamin D increases heart attacks, is that in everyone or only people at risk already for a heart attack?
Second, this suggests that we all need to be savvy with our health and make personal decisions based on our family history. For example, if your mother had breast cancer, then perhaps taking a calcium plus vitamin D supplement isn't a bad idea. If both of your parents suffered from cardiovascular disease, then probably not something you want to do (although drinking would be a good idea so you've got that going for you).
Think it over while enjoying a veggie frittata and high-fiber slice of toast...it seems we're all safe eating those foods (allergies not withstanding). At least this week. ;)
One of the best parts about living in Chicago is access to the country's top universities. Yesterday, I had the opportunity to hear a lecture by one of the area's top economists on the topic of math performance in girls and boys and future salary potential. As the mother of three daughters, I'm more than interested in this topic. As a scientist in a male-dominated career, I feel like somewhat of an expert already. But here's what I learned:
At this point in the lecture, a hairy spider walked across my table and I stood up like a crazy person and waved my arms around like an idiot until someone removed it (not even squished it, but gently took it away to live out its days in a planter or toilet). That is neither here nor there, but was a subtle reminder that you can take the scientist out of the lab, but you can't take the girl out of the scientist. The most interesting finding for me was that even after you factor out all of the reasons above, men still make more money than women at a given job. There is an underlying perception or expectation that men will outperform women. I'm sure if you compare 2011 to 1961, things are much better today and we are likely moving in the right direction for the future. But hearing these research results reminds me that women just need to work harder than men in a given career to achieve the same level of success. This is especially true in male-dominated careers like science and engineering.....and spider catching.
- There are no differences in math performance among girls and boys in elementary school. The evidence showing that boys may be slightly better than girls at math is noted at age 15.
- Boys are really only better at spatial ability (whereas girls are better at verbal). Interestingly, this is related to testosterone levels. Boys (and girls) with more testosterone are better at spatial ability than those with less testosterone.
- There is really no connection between spatial ability and math scores, EXCEPT in geometry. Tests, such as the SAT and ACT, that skew heavy on geometry result in higher scores for boys than girls. But when it comes to algebra and calculus, which have nothing to do with spatial ability, there are no measurable differences between girls and boys.
- When it comes to career salaries, there is a gender gap. Men make more money than women. Much of this is explained by the following:
- Women are less likely to take jobs with long hours or a competitive pay structure.
- Women are more likely to select jobs that are family-friendly versus those with higher pay.
- Women are more likely to step out of the work force for family reasons, which results in lower pay at a given point in time. For example, if you compare a 40 yr old man and woman who are both lawyers, the woman may make less money on paper, but she may have taken 5 years off to raise a kid or care for a sick relative and that is not always accounted for in surveys.
- In interviews, men tend to over-represent their experience resulting in better opportunities or higher pay, whereas women tend to under-represent their skills.
I'm a few days late in commenting on two studies that were published this week suggesting that vitamin and mineral supplements are harmful. One study tracked 38,000 women starting when they were 55-69 years. The researchers asked them to fill out questionnaires periodically on their supplement usage (and a bunch of other things) and then they just waited for them to die (morbid, but true). Results showed that after 20 years, those women taking a vitamin and mineral supplement had a 2.4% higher risk of death than those who didn't take a supplement. Iron seemed to be the nutrient most associated with a higher risk of dying earlier.
A different study looked at 35,000 men who either took a selenium supplement (200 ug/d), a vitamin E supplement (400 IU/day), both supplements, or none. After tracking these guys for 7 to 12 years, those taking either supplement (or both) had a higher risk of developing prostate cancer (17% higher risk for those taking the vitamin E).
The fun in being late to report on these studies is that I can respond to many of the comments that are being posted on various news sites and other blogs. Some range from rather insightful to loony. And I apologize to anyone who's words I'm using below...but I just couldn't let these go without commentary:
"I would like to know who funded the study. Could it have been a pharmaceutical company?"
Dr. T: Both studies were funded by the National Cancer Institute. Why on earth would a pharma company pay the millions of dollars needed for these large studies?
"Big pharma profits down, no new drugs in the pipeline, running out of people to over medicate, time to attack vitamins! The bottom line.This study is a classic example of scientific reductionism being used to fulfil a particular need. In this case, it’s supplement bashing, a well-known preoccupation of Big Pharma."
Dr. T: Ah of course, this is why. Pharma companies want people to get sick so they somehow convinced the National Cancer Institute to give millions of dollars to university professors who then were in on it too and designed a study to make people die more quickly from taking supplements...."a well-known preoccupation of Big Pharma". I hope this person declines any drugs their physician prescribes to them for a life-threatening disease (all developed and proven effective from a pharma company) since they feel so strongly about "scientific reductionism". And if someone could kindly explain what that term even means, I would greatly appreciate it.
"Vitamins should not be taken to INCREASE LIFE SPAN. Vitamins should be taken to enhance life."
Dr. T: This is true, no one ever said vitamins were going to extend your life. But if they do cut your life short, are they really enhancing your life?
"Maybe they died in car accidents going to buy more vitamins"
Dr. T: This is actually the smartest comment in the bunch. The study looking at women and supplement use did not evaluate whether vitamins CAUSED early death, but rather they were looking for whether there was an association. It is possible that women who were already sick happened to be taking more vitamins. Or that these women who take vitamins have other behaviors that increase their risk of death. That said, the prostate study coming out in the same week, plus earlier studies showing similar results, all suggest that people need to think twice before taking a supplement (see below for more info on that).
"This is utter BS. Bad science is plaguing the world. Especially that which pertains to the use of vitamins.Countless studies of vitamin megadoses show phenomenally positive effects on human health. Of course, these are predominantly unheard studies as the pharmaceutical industry will stop at nothing to keep people on their meds instead of letting them take preventative measures with vitamins, natural assets that give our bodies the strength to fight disease."
Dr. T: It is possible this is the same person with the same conspiracy theory above. First off, these two studies are some of the highest quality research out there since they have tens of thousands of people. There are NO studies with tens of thousands of subjects looking at megadosing of vitamins. In fact, most of those studies have 10 to 50 people and results seem to always work best in people that are already deficient. For example, mega-dosing of iron helps children grow and learn in less developed countries (because they are low in iron). And finally, these studies are being published in top tier journals that are run independently by university professors...not pharma companies. And what exactly is a "natural asset"?
So back to the title...should you stop taking your supplements? Maybe. Some things to consider:
1. Do you drink fancy drinks containing vitamins, eat energy bars with vitamins, have a bowl of fortified breakfast cereal every day? If so, you really don't need a supplement.
2. You really don't need more than ~100% of the daily value in a supplement. If you are taking more than that, you may want to re-consider what you are taking.
3. You may only need to supplement selected vitamins and minerals. For example, a vitamin D supplement is really only needed for those living in northern locations or those who are never outside without sunscreen. Women who are menstruating and do not consume red meat probably need to take iron but men do not. Those who do not eat any fruits and vegetables (gasp!) should take a vitamin C supplement but if you are smart enough to eat those foods, you probably don't.
4. Is a "whole-food supplement" better than a regular supplement? At this point, we don't know. There are no big studies looking at food-based sources of vitamins and minerals and health. It may be that it doesn't matter where the vitamins come from. Or they may be better, but not clear yet. I would still stick to the 3 principles above until we have more information.
And I promised a friend I would look at natural remedies for cold and flu so hope to get to that topic next!
There's no doubt that young girls these days are maturing a lot faster than when we were little. On average, puberty is starting as young as 9 years in Caucasions and 8 years in African-Americans (and that's an average, so for some individuals, it starts much sooner). Just look at the bra section in Justice...it seems to get bigger each year.
A number of theories exist as to why this is happening, most notably the increase in childhood obesity. Young girls who are obese have a much higher risk of developing early versus non-obese peers. Fat cells produce estrogen, which may kick off the puberty process early. Young boys who are obese may have delayed puberty for the same reason...however the estrogen blocks testosterone from initiating puberty. Either way, those of you with children would probably agree that they are happiest when they are 'average'. Early puberty or late puberty does not make for a happy child and therefore by default, a happy parent.
Other theories for why puberty is starting earlier include things like pesticides, hormones in milk, and other contaminants in our environment. And it may not just be whether the children themselves are exposed to these contaminants, but both parents as well.
A new study this month is suggesting another possible cause for early puberty: low levels of vitamin D. The research showed that girls in northern latitudes (where there is much less sun and therefore less vitamin D being made in the skin) are more likely to have their first period earlier than those in southern latitudes. This is a very important finding because girls who have their first period before age 12 have a much higher risk of breast cancer later in life.
This study doesn't prove that taking a vitamin D supplement will delay a girl's first period, but it does provide more rationale for why its important for girls to drink milk (which has vitamin D) and/or take a multi-vitamin containing vitamin D. These results also suggest that children in northern climates may benefit from having vitamin D levels tested at the pediatrician's office to rule out a deficiency.
And most importantly (for me anyway), this is a darn good reason for a winter vacation in a nice climate!
This one goes out to Megan, a personal trainer based in London. She's been hearing a lot about the Paleolithic Diet and wants to know the real scoop. Here goes...
The Paleolithic Diet is also called the Caveman Diet, Stone Age Diet, or Hunter-Gatherer Diet. It is based on what humans used to eat prior to the agricultural revolution and after humans learned to use stone tools...so we're talking at least 10,000 years ago. Although there's considerable debate, most nutritional anthropologists agree that this includes animal flesh (four-legged, two-legged, and finned creatures), vegetables, roots, fruit, and nuts.
Proponents of the diet claim that our ancestors thrived on these foods and had no evidence of the diseases that plague our society today; most notably, obesity, heart disease, and diabetes. They also claim that our DNA is best suited to utilize these foods and reject foods not available during that period such as grains, dairy, legumes, refined sugars and oils. They argue that our DNA has not changed but the food supply has, and we are not genetically adapted to these "new foods". Bottom line, they feel we'd all be better off eating the foods that make our DNA happy.
The diet itself ends up being very high in plant foods (good), protein (good), and fiber (good) and contains no processed food (very good). The downsides are the diet is inherently low in calcium (not good) and vitamin D (not good). Some minor modification of the diet could increase calcium and vitamin D intake, or a dietary supplement could serve the same role. The diet can also be difficult to follow if you are on a tight food budget or do not have access to the limited list of foods all year round.
What does the research say? There's really little to go on. There have been a handful of studies, but all of them are with very few people. One of the more interesting studies looked at the effects of the Paleolithic Diet compared to a Mediterranean Diet in folks with heart disease. Those that followed the Paleolithic Diet reported being less hungry and they actually consumed less calories. The researchers did not report any information about their heart disease symptoms so its difficult to conclude whether the diet is better or worse than the Mediterranean Diet for heart disease.
Other studies have shown that people with type 2 diabetes had better blood sugar control with the Paleolithic Diet versus a higher carbohydrate diet. But again, there were very few subjects in the study so its hard to generalize these results.
There have been far greater numbers of studies showing that dairy foods, whole grains, and legumes (banned on the Paleolithic Diet) can be part of a healthy diet that reduces the risk for obesity, heart disease, and diabetes. So based on the scientific evidence to date, there does not appear to be a strong rationale for everyone switching to the Paleolithic Diet. That said, there doesn't appear to be a big risk in following that diet for those who find it appealing.
Some folks will probably feel awesome on the diet and others will not....this is how our DNA really works. Based on our individual genetics, which includes how we taste and metabolize food, some diets may be a better fit than others. If you enjoy eating roots, vegetables, fruit, nuts, fish and poultry/meat, then the Paleolithic Diet may be worth a go for a few weeks to see how you feel.
Has anyone tried it? Any insights?
Good luck Megan!