The Low-Carb Movement Has Made Sugar and starches the New Nutritional Villain. While Appropriate Advice for Most People, Others Can Get Away With Some Starches or Should Even Be Eating More. How Can This Be Determined?

Nutrition has two components: macronutrients and micronutrients.

Micronutrients are the elements of food that supply necessary minerals, vitamins, and other necessary molecules and biochemicals. The best way, indeed the only way to do this is to eat a diet consisting of a broad variety of vegetables and meats, with meats including mammals, fish, fowl, dairy, and eggs. With the possible exception of vitamin D, no supplements have been shown to have any benefit, and a rather frightening number of them have been shown to be harmful.

Macronutrients Are Our Energy Source.

Our cells are all set up to create cellular energy, called ATP, from fats, glucose, and protein. The cells prefer them in that order. Fats burn cleanest and, if not accompanied by glucose, will not cause weight gain. Glucose is a form of sugar. All starches and sugars are converted into glucose by the time they get into the bloodstream.

We are evolved to efficiently utilize fat. Other animals have other schemes. Hummingbirds, for instance, live up to 20 years on a diet of almost 90% sugar, and bats live a similarly long time on a 100% protein diet (bugs). But not us. For hundreds of thousands of years, we lived in a world where starches and sugars were rare, but game, fish, and leafy forest vegetables were not. We evolved big brains so we could catch or gather these, and we evolved dietary metabolism and storage systems optimized around this diet.

Starches Have Little Micronutritional Value

A potato has some value. Most processed starches, such as breakfast cereals, are almost valueless beyond what was added for “fortification.” Starches, therefore, are primarily macronutrients. For some, perhaps most, starches and sugars are not efficiently metabolized. This is due to three factors, two of which we cannot control. First, as mentioned above, we are genetically predisposed to a protein/fat diet. We simply aren’t inherently good at using the glucose that starch is converted into. Second, we age. Cells lose efficiency. The third factor is the abundance of sugars and starches in the Western diet. We have total control over this.

Some People Should Eat Starches

Someone who is very thin (if elderly, one might say frail) should eat healthy starches. A potato a day, say. This would especially be the case if energy is low. This can be determined by measuring fasting insulin levels. Fasting insulin should be between 3 and 6 µu/ml. If it is higher, glucose is getting stored as fat. If it is lower, as would be the case with an overly thin or frail person, insulin is not high enough to permit the body to rebuild. Not good at all. An increased dose of starches will cure this.

Most Children Can Get Away with Eating Starches (To Some Extent)

Children have nice, fresh, healthy cells, tend to be highly active, and are usually low stress. (Not what my kids tell me, by the way. Dr. M.) This combination makes their starch metabolism much more efficient. However, cells adjust to the nutrients they are getting, and this can lead to a “give me glucose and only glucose” trap. Additionally, children need an abundance of micronutrients. So even though a diet fairly high in starches will not necessarily cause excess blood glucose and fat storage, the cellular programming may cause them to shun healthier food in favor of the quick glucose “fix.” Most parents fight this “gimme carbs, carbs, carbs” sort of behavior, and this is certainly to their children’s benefit.

What about the Rest of Us?

There are two pretty accurate ways to tell: a blood test or a seemingly slow but persistent weight gain. The blood test will measure the amount of circulating sugar. The body will usually not let it drop below a certain level, and will do all sorts of bio-chemical magic to keep it there (such as making glucose from fat). This ideal level is between 60 and 80 mg/dl. Higher than this is fat storage territory, and people in this category should eat less starch and sugar. How much less? Enough to bring the glucose levels in line. For some, a mild cut. For others, complete starch and sugar abstinence.

Average sugar is also frequently measured. This should be below 100 mg/dl. This is also called hemoglobin A1C or just A1C. Often the number is given in percent, with 5.1% corresponding to 100 mg/dl.

The second method for noticing a starch issue is to spot a weight gain pattern. Many people stay nice and trim into their twenties, and then a couple of pounds a year starts creeping in. In a decade, this has become 10 to 20 pounds, and so on. Not an unfamiliar pattern. This is almost always a sign of excess glucose. Because of our hunter-gather heritage, excess glucose is stored as fat. A lack of exercise or high stress will exacerbate this, and both of these are far too common in our multitasking, gadget-ridden Western society.

Either way, the cure is clear. Cut the sugar. Cut the starch. This includes whole grain. Though better than refined grain, it is only slightly better, and good quality colorful vegetables are a whole lot better than either.

You may note that starch appears as the major component in the Food Pyramid, and, though occupying lesser position, is still a prominent member component in the “Myplate” replacement. Pardon us for yelling, but, GRAIN IS NOT A FOOD GROUP. It is a branch of the Vegetable Kingdom, and a sinister one at that. It only got to its place of undeserved prominence by industry pressure. Grain has been foisted on the unsuspecting masses from the Agricultural Revolution onward. It was, and still is, a cheap way to feed a large number of people. But it is definitely not a GOOD way, despite its endless favorable publicity.

So high blood glucose or persistent weight gain are both good reasons to get starch and sugars out of the diet. However, there are other harms possible from a high starch diet, so other than people that need the added macronutrients, there is no harm from cutting starches, and most likely considerable benefit.

Making the Switch Can Be Tough

The cells literally program themselves to use the sort of fuel they are getting and won’t switch overnight. A switch from primarily glucose to fat, though healthy, will lead to a temporary sugar craving. Some experience none at all. For others, it lasts up to three months.

The Brain Needs Glucose, Right?

Wrong. But it needs something for energy, obviously, and rest assured, it will get it. It can run on glucose, smaller fat molecules, and ketones. It has a very high priority, and even if no glucose is eaten at all, the body will manufacture one of the three above nutrients in sufficient quantity. In fact, the brain may run better on ketones. People with dementia display significant cogitative improvement on such a diet.