dairy Archives - What We Eat NYC

When I worked as a primary care dietitian, not a day passed without me recommending the substitution of low-fat or nonfat dairy products for their full-fat counterparts. Whether I was seeing someone with heart disease or high cholesterol, obesity or diabetes, choosing low-fat/nonfat dairy was a no-brainer. However, a growing body of evidence suggests this recommendation may be at best ineffective, and at worst counterproductive.

There were two main reasons the medical field touted the superiority of low-fat dairy for so long:

Saturated fat has long been associated with high cholesterol and heart disease. Full fat dairy is higher in saturated fat than low-fat/nonfat dairy.
Low calorie diets are associated with healthy weight management. Full fat dairy is higher in calories than low-fat/nonfat dairy.

What’s changed? The short answer is nutrition science itself. Until recently, nutrition science has focused on isolated nutrients instead of actual foods.

In the case of saturated fat and heart disease, science looked at the effect of saturated fat overall. It did not distinguish whether it came from animal fat (think the fatty gristle on a t-bone steak), dairy fat (think whole milk) or vegetable fat (think coconut oil). All foods have unique fatty acid profiles, each of which may have different metabolic effects. Even a food group’s subsets, like milk, yogurt, cheese and butter, which all fall under the dairy umbrella, have different profiles and different effects. When the full fat dairy group is teased out from the other saturated fat sources, it does not appear to be significantly related to risk of heart disease.

In the case of calories and weight control, science has long held that a calorie, is a calorie, is a calorie. Fat has more calories per gram than protein and carbohydrates (9 calories per gram versus 4 calories per gram), so therefore reducing calories by choosing lower fat alternatives was thought to aid in weight management. However, new research indicates that full fat dairy is associated with improved weight control. While the reason isn’t fully understood, one hypothesis is that full fat dairy is more filling than low-fat/non fat dairy alternatives, so those who consume the latter compensate by eating more calories (most often from refined carbohydrates) later on.

So, what’s a dairy eater to do? Here are my recommendations:

Enjoy full fat versions of the dairy you currently consume if you’d like. Three servings of dairy is great. That could be one cup whole Greek yogurt for breakfast, a small whole milk cappuccino midmorning and an ounce or two of cheese crumbled atop a salad for dinner.
Fermented plain full fat dairy like yogurt and kefir seems to be the most beneficial of all full fat dairy products, so extra points for regularly including these foods in your diet.
Limit low-fat/nonfat and full fat dairy with added sugars or sugar substitutes.
The bulk of your diet should be vegetables and fruit (at least half), whole grains, nuts and seeds, legumes and other lean proteins like fish and eggs. These foods are indisputably good for you.

One final note. Nutrition science is so young. The direction of research today indicates that full fat dairy isn’t the no-no we once thought it was but that doesn’t mean we should accept this as indisputable fact for life. Nutrition science will continue to evolve so it’s important to be open to new developments but at the same time be skeptical about where your information is coming from. As Dr. David Katz, Director of Yale University’s Yale-Griffin Prevention Research Center, says:

“It is the least substantiated, most uninformed opinions about how to eat that will come at you with the greatest conviction. That’s your first clue that something is awry, because true expertise always allows for doubt.”

xo Laura

The thing about carbohydrates is not all carbohydrates are created equal. (Not all proteins or fats are created equal either, but let’s save that for another blog post.) Carbs come in every variety, from very health enhancing to less so. That’s why any diet that banishes them entirely will, yes, cut out a good amount of play food. But it will also lead you to miss out on lots of important nutrients (honestly, the details of which don’t matter), and unnecessarily eliminate foods that are truly enjoyable. So let’s break them down…

What foods contain carbohydrates?

Fruits
Vegetables
Whole Grains
Legumes (aka beans and nuts)
Dairy (this one surprises people sometimes but lactose is a carb)
And every food derived from the above (e.g. juice, sugar derived from the sugar cane plant and all other caloric sweeteners, potato chips, breakfast cereals, snack foods like crackers and cookies, breads from white to whole wheat, pastas, etc.)

“Complex” carbs versus “simple” carbs

We’re often told to choose “complex” carbs (carbs that have three or more sugar units strung together) and to abstain from “simple” carbs (carbs made up of only one or two sugar units). But let me give you an example of why this blanket recommendation doesn’t work. White bread, made up of starch, is technically a “complex” carb. Apples, made up of glucose and fructose, are technically “simple” carbs. Few would argue that white bread is a healthier choice than an apple. It’s not.

White bread is made with white flour. White flour is made by removing the healthiest components of a wheat berry: the fiber, nutrient-filled bran and germ. What is left–the energy-filled endosperm–is then ground into a fine dust. Essentially, even before we take our first bite of toast, a great percentage of our bodies’ digestion has already been completed by outside processing. So the “complex” carbs in white bread are very readily absorbed and quickly converted into sugar in our blood streams, what doctor’s call blood sugar or blood glucose.

An apple is made from, well, an apple. When we eat it, besides the obvious fact that our teeth have more work to do to ready it for swallowing, our GI tracts also have to work harder to separate the “simple” carbs from the fiber, water and other nutrients packaged with them. This, among other reasons, leads to slower absorption and conversion of the “simple” carbs of the apple into blood sugar. Rest assured, our bodies will absorb all of the good stuff, it just takes more time. More time is a good thing.

Why it matters whether our blood sugar increases quickly versus overtime

Blood sugar fuels the activity of our bodies’ cells, but it can’t get into them without some help. Insulin, a hormone made by the pancreas, acts as a key to open up cell doors and let blood sugar in. Because our bodies don’t like a ton of sugar hanging out in our blood stream, a surge in blood sugar from foods like white bread leads the pancreas to release a corresponding surge in insulin. All of the sugar is quickly ushered out of our blood stream and into our cells. Before you know it, the highway that is our blood stream is free of sugar. This wouldn’t seem like a bad thing, but our bodies actually prefer there to be a little blood sugar traffic. If there is no blood sugar available to cells, what would happen if all of a sudden our bodies needed more energy? So, low blood sugar triggers additional hormonal responses in our bodies – hormones that make us hungry. This explains why most of us feel starved only a few hours after having a muffin for breakfast.

Alternatively, when we eat foods like apples that are full of nutrients like fiber that take longer to break down, our blood sugar rises slowly and steadily overtime. Correspondingly, our pancreas releases insulin slowly and overtime. There is a steady flow of light blood sugar traffic in our blood stream. When insulin moves some blood sugar into our cells, a little more blood sugar merges onto the highway from our GI tract to replace it. This translates to our blood sugar rising and falling slowly and overtime. Why is this so great? Our bodies tell us that they are satisfied for longer.

A better way to think about carbs

So, here is a clearer carb recommendation: Eat carbohydrate foods that have undergone as little processing as possible the majority of the time –

Fruits
Vegetables
Whole Grains
Legumes (aka beans and nuts)
Low fat milk and yogurt

– and the ones made by processing them, less often –

Juice, even smoothies
All sugars from white to agave to honey
Traditional snack foods like potato chips, pretzels, crackers
Bakes goods like cookies, cakes, doughnuts
Breakfast cereals
Breads from white to whole wheat
Pastas and white rice
Etc.

The former are like time-release energy/fullness pills and the latter are like fast-acting energy/hunger-inducing pills. Maybe this means you choose to do an 80/20 split, or 90/10, that’s all up to you. The good news is there’s no good reason to give up carbohydrates.