If you don’t like a particular nutrition research finding—say, one that demonizes a certain food you love—then wait 5 minutes. A new finding might modify, limit, or completely reverse it.
Witness the latest trifecta of nutrition controversies: one involving cholesterol in food (no longer a health concern?), a second on saturated fats (are they really that bad for you after all?), and the third on salt (have the guidelines been overly stringent?).
I’ve been thinking a lot about these three in particular since they’ve been associated with increased disease risk. Or so we thought. (By the way, curious about recent competing claims and controversies over canola oil, probiotics, gluten, intermittent or “mini” fasting, etc.? Write me and ask about them.)
So, what really matters with cholesterol, fats, and salt? I think it’s what has generally mattered all along, the larger truths that 1) stand the test of time and 2) do not leap to all-or-nothing claims about one nutrient group or another. To find and hold the sensible “middle ground”—and avoid the shifting terrain at the controversial edges of nutrition science—requires a holistic view centered on balanced eating.
Let’s take cholesterol.
The buzz: Eating foods high in cholesterol (e.g., eggs, shrimp, lobster) does not significantly affect blood-level cholesterol or increase heart disease risk.
The bigger truth: Cholesterol molecules don’t dissolve in blood, so they have to be transported as part of a “lipoprotein complex.” While the cholesterol you eat does have its own lipoprotein pathway for getting into your blood, what really matters is the balance in your blood between low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL, or what we think of as “bad” cholesterol, is only bad when there’s too much of it since the excess tends to get deposited in blood vessel walls. And yet if there’s enough HDL (or “good” cholesterol) around, it can scavenge up even this deposited cholesterol for healthy re-use. So while eating a moderate amount of cholesterol in food will not destabilize your blood cholesterol balance, the bigger (and better) truth, though it’s not news, is that you can actually increase HDL through diet and exercise and thereby improve your blood cholesterol balance.
Now look at saturated fats.
The buzz: In April 2014, a mega-review of multiple clinical trials and medical studies (i.e., a meta-analysis) appeared in the prestigious medical journal Annals of Internal Medicine. The authors concluded that this huge body of evidence “does not clearly support” guidelines that encourage a low consumption of total saturated fats. This got headlined in the peoples’ press as “No link found between saturated fat and heart disease.” A firestorm of protest, pointing to errors of fact, methodology, and interpretation, erupted from the nutrition science establishment, including a call for the entire review to be retracted.
The bigger truth: Sorting out the claims and counterclaims on this one would take a book. But I can distill for you some recurring themes that appear in the link above and make up bigger truth in this case. Once again it doesn’t work to look at just one nutrient group of interest apart from what else is changing in the nutrition balance. For example, studies that decreased saturated fat intake by increasing carbs (a “no-fat” diet) found no change in the HDL-to-LDL balance; similarly, replacing saturated fats with sugar and refined carbohydrates did not reduce risk of heart disease. But the main refrain highlighted study results showing that eating foods containing healthy levels of unsaturated fats like those associated with a Mediterranean diet (e.g., nuts, extra virgin olive oil, seeds, avocado) is healthier than eating the same level of fat in saturated fats. And a large review last year found that Mediterranean-style eating reduced heart attacks and strokes, compared with eating less fat but more starches. Finally, there’s no controversy at all about the link between heart disease and the transfats and partially hydrogenated oils added to processed foods.
And then there’s salt.
The buzz: Lowering salt intake to levels recommended by the Federal Government (not more than 1,500 mg a day) may in fact increase the chance of cardiovascular disease.
The bigger truth: No one is saying that salt intake doesn’t matter at any level. The issue is whether the recommended daily max should be around 1,500 mg of sodium or perhaps double that, around 3,000 to maybe 4,000 mg of sodium at most. Remember, just one teaspoon of ordinary table salt is 2,300 mg of sodium. But that raises a key point: the primary source of salt intake for Americans is not the salt shaker, it’s the salt in processed foods, including nearly all of our fast-food restaurant favorites. And what are those sources of “hidden salt” also likely to contain? That’s right: added sugars and (for fried fast foods) trans fats. So beat the bloat this summer and avoid the salt and sodium in packaged, canned, and other convenience foods.
How to transcend the trendy? Don’t swing with the latest headline. Instead, eat REAL food as part of a balanced and colorful diet, and always aim for the purest (most natural) form of that food, thereby avoiding over-processed, deep fried, pulverized, prepackaged, over-sugared, and over-dressed options. And as always…
…keep movin’ – Jen