Atkins Diabetes Revolution (24 page)

Note: Your individual results may vary from those reported here. As stated previously, Atkins recommends initial laboratory evaluation and subsequent follow-up in conjunction with your health care provider.

Chapter 12

THE IMPORTANCE OF GOOD FATS

Dietary fat is one of the most important tools you have for controlling your insulin and blood sugar. That might seem impossible, given the simplistic antifat message that has been relentlessly hammered into our collective consciousness for so long. The reality is that most fats— in fact,all natural fats—are fine when carb intake is controlled.In fact, natural fats are absolutely necessary for good health, and are actually helpful for preventing and treating diabetes.

CHEMISTRY 101: DIETARY FATS

Fats are oily, organic compounds that don’t dissolve in water—think of the way oil floats on top of water—but do dissolve in other oils. Fatty acids (the chemist’s way of describing fats) are long chains of carbon and hydrogen atoms with some oxygen atoms stuck on at one end. (Technically speaking, it’s the oxygen at the end that makes the molecule an acid.) How many hydrogen atoms the chain contains,and where those atoms are located on the chain, determines what sort of fat it is.

The natural fats we regularly eat fall into three basic categories:

• Saturated fats.
  Almost all of these fats are solid at room temperature; butter, lard, and suet are good examples. They are solid because the carbon-and-hydrogen chain contains as many atoms as it possibly can. This is why it’s called “saturated.” Although we tend to think of saturated fats as animal fats, a few vegetable oils, such as coconut oil and palm oil,are also highly saturated.Unlike saturated animal fats, they stay liquid at room temperature.
  
• Monounsaturated fats (MUFA).
  Liquid at room temperature, monounsaturated fats include olive oil and the oils found in nuts and seeds; avocados also contain monounsaturated fat. These fats are monounsaturated because a single carbon atom somewhere in the chain has a double bond, meaning that the chain is missing a hydrogen atom.
  
• Polyunsaturated fats (PUFA).
  Polyunsaturated fats are also liquid at room temperature. Canola oil and safflower oil are polyunsaturated fats, as is flaxseed oil. The oil found in fatty fish is also polyunsaturated. These fats are polyunsaturated because more than one carbon atom along the chain has a double bond, so more hydrogen atoms are missing. The number of double bonds and where they are in the chain determines the type of polyun- saturated fat.
  

THE ESSENTIALS

Just as your body absolutely must have vitamins every day, and just as you can get those vitamins only from food or from supplements, your body also needs certain dietary fats.These essential fatty acids,as nutritionists call them, are basically two types of polyunsaturated fats: omega-3 fatty acids (also called alpha linolenic acids or n-3 fatty acids) and omega-6 fatty acids (also called gamma linoleic acids or n-6 fatty acids).These fatty acids support a range of crucial bodily functions.You need them to make cell membranes, to make the oxygen-transporting hemoglobin in your red blood cells, and to make eicosanoids and
prostaglandins—natural chemicals that play a crucial role in regulating many body functions such as inflammation.

Omega-3 fatty acids are found in eggs, fish, vegetable oils, nuts and seeds, and dark green leafy vegetables. The main dietary sources of omega-6 fatty acids are vegetable oils, such as soybean oil, canola oil, and safflower oil. In the modern diet, the balance of these fats is sadly off-kilter. Because omega-6 fatty acids are found in the cheap, highly processed vegetable oils that are used in so many prepared and processed foods,the average American now eats about 16 times as much omega-6 fatty acids as omega-3s, instead of a more natural ratio of about one to one.
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When you get rid of the processed,high-carb foods in your diet, you shift your intake of essential fatty acids away from these lopsided proportions and back toward a more desirable ratio. To be on the safe side,consider taking a balanced essential fatty acid supplement. (For more on essential fatty acid supplements,see Chapter 20.)

Omega-9 fatty acids aren’t essential, but we recommend getting plenty of them in your diet.Good dietary sources of omega-9s are extra- virgin olive oil, sesame oil, peanuts, all tree nuts, and avocados. There are also some omega-9 fatty acids in poultry and pork.

A QUICK COURSE IN CHOLESTEROL

We’ve talked a lot about cholesterol already, and we’ll be talking about it even more in the chapters that follow. It’s time to get down to some details about this controversial yet vital substance.

• Cholesterol is a waxy chemical compound manufactured by your body—it’s not really a fat at all, and your body doesn’t burn it for energy as it does with fats.
  
• Cholesterol is essential for a wide variety of crucial functions, including manufacturing the hormones testosterone, estrogen, and progesterone, making cell walls and brain tissue, and producing vitamin D in your body.
  
• Your body manufactures most of its own cholesterol. However, a small amount comes from the cholesterol you digest, found in animal foods like meat, dairy products, and egg yolks.
  
• Your body makes cholesterol as it needs it, mostly in your liver, at the rate of about 800 mg to 1,500 mg a day. The average American also eats about 300 mg to 450 mg or more of cholesterol daily, but of that amount, no more than half—and perhaps only as little as 10 percent—is actually absorbed by your body.
  

To move waxy cholesterol through your watery bloodstream, your body turns it into lipoproteins—complexes of cholesterol and protein. There are several kinds of lipoproteins, but the two most important are low-density lipoprotein, or LDL cholesterol, and high-density lipoprotein, or HDL cholesterol. Just to remind you, LDL cholesterol carries fat and cholesterol
from
your liver, where most of your cholesterol is manufactured,to the parts of your body that need it.HDL cholesterol carries unused cholesterol
back
to your liver, where about half of it then gets recycled again into LDL cholesterol; some is excreted in the bile acids used in digestion, and some is recycled for other purposes. While it is true that high levels of LDL cholesterol can be bad, and that low levels of HDL are also undesirable, the story is a lot more complex: See Chapter 9, The Cardiac Connection.

CHOLESTEROL BY THE NUMBERS

According to the latest recommendations from the National Cholesterol Education Program (NCEP III),here’s what your blood lipids should be:

• Total cholesterol (HDL and LDL combined): less than 200 mg/dL
  
• LDL cholesterol: less than 100 to 130 mg/dL
  
• HDL cholesterol: 40 mg/dL or more for a man; 50 mg/dL or more for a woman
  
• Triglycerides: less than 150 mg/dL
  

GOOD FATS AND BAD FATS

If you have a rudimentary understanding of fats, you’ve probably picked up the standard take on the subject. That is, saturated fat is bad and mono- and polyunsaturated fats are good. That popular oversimplification is very misleading. For one thing, all naturally occurring fats are actually mixtures of different kinds of fatty acids. The fat found in beef,for instance,contains a mixture of saturated and monounsaturated fats—in fact, there’s actually more
unsaturated
fat (whether from monos or polys) in beef than saturated. Beef fat is solid at room temperature, however, so it’s misleadingly lumped into the saturated fat category.

The standard dietary advice comes down especially hard on saturated fats. That’s because a diet high in saturated fats and cholesterol from animal foods is often linked with heart disease. But that link is tenuous at best. The much-touted connection between saturated fat and cholesterol in the diet and high cholesterol levels and heart disease is a lot less solid than you might think. Respected science writer Gary Taubes pointed this out in a watershed article published in the
New York Times Magazine
in July 2002, entitled “What If It’s All Been a Big Fat Lie?” One significant problem with most studies that claim saturated fat raises cholesterol levels is that they don’t take into account carbohydrate consumption. Saturated fat can indeed raise blood cholesterol—when it’s eaten in the context of a high-carb diet.
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,
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To date, in studies looking at the Atkins protocol, saturated fat had little impact on cholesterol levels.

In these same studies, dietary fat had little or no effect on raising blood lipids.You should eat a balance of fats; fortunately, Mother Nature makes that easy for you.You may not know, for example, that in a 31?2-ounce pork chop containing 22 grams of fat, only 8 grams are saturated. Another 10 grams are monounsaturated fat and the rest are polyunsaturated fat. You don’t have to worry about achieving a good balance of fats if you simply eat a variety of protein foods and also consume olive oil, olives, avocados, and nuts.

Nor is there any real reason to restrict saturated fat when you’re following the Atkins Blood Sugar Control Program properly. There’s very little evidence to show that eating saturated fat in balance with other natural fats is harmful to your health. In fact, some studies show that even when carbs are not controlled, a moderate amount of saturated fat can raise LDL cholesterol, but it is compensated for with an increase in HDL cholesterol.
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And recently, researchers reported to their surprise that eating a diet high in total fat or high in any particular type of fat (including saturated fat) has little or no effect on the risk of stroke.
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If you’ve been diagnosed with the metabolic syndrome, prediabetes, or diabetes, your lipid levels and insulin/blood sugar levels aren’t what they should be. But avoiding foods containing cholesterol and saturated fat isn’t the answer—in fact, avoiding protein-rich, fat- rich foods in favor of carbohydrates could well make your health problems worse. What will help get your blood sugar under control and improve your blood lipids is
balancing
dietary fat in conjunction with the ABSCP.

RESEARCH REPORT: FATS AND DIABETES

Fat in the diet has long been blamed as a cause of diabetes. When researchers look more carefully,however,they find that the evidence actually points in the opposite direction. Dietary fat does
not
increase your risk of diabetes, and adding
certain fats
to your diet might actually help prevent diabetes. To take one example, researchers who were looking at data from the long-running Nurses’Health Study found,after following over 84,000 women for 14 years, that total fat intake wasn’t associated with an increased risk of Type 2 diabetes. They also found that the level of saturated and monounsaturated fat consumption wasn’t associated with a significantly higher risk of diabetes. What they did find was that higher intakes of polyunsaturated fat were associated with a
lower
risk of diabetes.In fact,all it took to reduce these women’s risk of diabetes by 35 percent was getting just 5 percent more of their daily calories from polyunsaturated fats. In other words, women who got more fat from sources such as fish and vegetable oils had a lower risk of diabetes. This same study also provides another reason to avoid added trans fats. The incidence of Type 2 diabetes could be reduced by at least 40 percent if oils were consumed only in their original unhydrogenated form.
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HELP FROM THE GOOD FATS

The protective effect of dietary fat was shown in a landmark study back in 1987. Researchers compared the effects on healthy men and women of a diet high in monounsaturated fat from olive oil with those of a diet low in dietary fat and high in carbohydrates. Both diets lowered LDL cholesterol, but the low-fat/high-carb diet had the undesirable effect of both lowering HDL cholesterol and sharply increasing triglycerides.
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If you have the metabolic syndrome, prediabetes, or diabetes, you probably have low HDL and high triglycerides along with LDL that is normal or slightly on the high side. It’s pretty clear that eating a lowfat, high-carb diet won’t do much to help your blood lipids. That diet is more likely to make things worse—including your blood sugar.

PROCESSED VS. UNREFINED OILS

To prolong their shelf life and allow for heating at higher temperatures, most of the oils found in supermarkets have been heavily processed.It is best to avoid them. Instead, look for cold-pressed vegetable or nut oils, which have not been exposed to heat or treated with chemicals. Cold- pressed oils are preferable because they retain more nutrients and flavor. Expeller-pressed oils have been exposed to heat, but retain more of their flavor than refined oils do. To keep unrefined oils fresh, buy in small quantities,refrigerate after opening,and store in opaque containers. Fats become rancid when exposed to too much heat or light, are reused, or are kept too long. Eating rancid fats can increase the risk of heart disease.

GO NUTS!

Nuts are the ideal snack food when you’re following the ABSCP. These delicious,crunchy morsels are crammed with unsaturated fats—in fact, up to 80 percent of the calories in nuts can come from the fat (see the chart below).They’re fairly low in carbs,and because they’re also high in fiber, they are low in Net Carbs. Their glycemic load is low too; on the AGR (Atkins Glycemic Ranking), most nuts are in the “eat regularly” column.(So are delicious oily seeds,such as sunflower seeds and pumpkin seeds; coconut also falls into this category.) The fiber in nuts helps slow the entry of the carbohydrates into your bloodstream, acting as a sort of time-release mechanism that delivers the carbs in a slow, steady way. Nuts also contain good amounts of trace minerals such as magnesium and selenium that may be helpful for people with, or at risk for, diabetes.