Monday, November 18, 2013

Try a bigger breakfast

When you eat a day’s worth of food really does make a difference, according to Daniela Jacubowicz, a professor at Tel Aviv University.  In a recent study, published in the journal Obesity, she randomized 93 overweight and obese women into 2 groups and followed them for 12 weeks.  Both groups ate 1400 calories a day, consuming a healthy variety of poultry, fish, egg whites, vegetables, fruits and whole grains.  The ‘breakfast group’ had 700 calories for breakfast, 500 for lunch and 200 for dinner.  A sweet treat was included as part of their breakfast, such as a small chocolate bar, to stave off cravings for the rest of the day. The ’dinner group’ had exactly the same foods in reverse order - 200 calories for breakfast, 500 for lunch and 700 for dinner.  I presume that their chocolate bar came with dinner.

At the end of 12 weeks, the results were striking.  The ‘breakfast group’ lost an average of 19 pounds while the ‘dinner group’ lost 8.  Waist circumference decreased by 3 inches in the ‘breakfast group’ compared to 1.4  inches in the ‘dinner group’.  Glucose and insulin levels dropped significantly more in the ‘breakfast group’.  They did not experience the high spikes in glucose levels that can happen after a meal and are considered dangerous. Triglyceride levels fell 34% in the ‘breakfast group’ but increased by 15% in the ‘dinner group’.  Triglycerides are a main form of fat in the body; high levels of triglycerides have been associated with greater risk for heart disease. Average hunger scores were significantly lower in the ‘breakfast group’. 

The authors of this study concluded that a high calorie breakfast with reduced intake at night is a useful alternative for the management of obesity.  Previous studies from Tel Aviv University also looked at overweight men, and came to similar conclusions. In summary, our metabolism is impacted by the body’s 24 hour circadian rhythm. The time of day we eat can have a real impact on the way our bodies process food.

What are the implications of this study for you, the reader?  I am not suggesting a 1400 calorie diet, but a change in when you eat the amount of food that is right for you. Your weight may be just right, or you may be overweight, or too thin.  You may be a person who is never hungry in the morning, or who really relishes a big dinner at the end of a busy day.  I think it makes sense to ease your way into bigger breakfasts and lighter dinners because of the benefits on glucose and insulin levels, and because of the greater energy you will experience after a hearty (healthy) breakfast.  If you are never hungry in the morning, try a very light dinner one night, such as a bowl of cereal or a dish of cooked vegetables.  You will probably wake with an appetite.  If your usual breakfast is toast and tea, or a pastry and coffee, you may notice that your energy drops mid morning and more coffee is needed to keep you going.  When you add healthy protein and whole grains to your breakfast you will notice a smoother feeling of energy that lasts until your next meal.  What to do about the big dinner you have always loved?  When you start to follow this plan, you may find that you want to make it simpler and smaller without too much difficulty.  You may like spending less time cooking. Another benefit from a smaller dinner is feeling more energy in the evening. Having a lot to digest at night makes some people sleepy. 

Finally, Professor Jacubowicz suggests an end to late night snacking, in front of the computer or television.  She feels that this is a major contributor to the obesity epidemic, causing weight gain and a greater risk of cardiovascular disease, due to the midnight spike in blood sugar. 
Sadja Greenwood, back issues at

Monday, November 4, 2013

Appreciating Blood

As blood flows from the heart through arteries, capillaries and veins, this amazing substance keeps us alive. The beautiful red color of blood is due to the iron in hemoglobin, the molecule in red cells that carries oxygen.
Blood delivers oxygen, hormones and nutrients to body cells and picks up waste products from them.  White blood cells contain the many elements of the immune system.  Blood helps to control body temperature.  It carries a clotting system to control blood loss after injury. 

As blood travels throughout the body, its red cells deliver oxygen to all body cells and remove carbon dioxide.  After returning to the heart, blood travels to the lungs, giving off carbon dioxide and picking up fresh oxygen. Blood picks up digestive products from the intestines and carries them to cells for metabolism/energy production.  At the same time, it removes waste products from cells and delivers them to the kidneys for excretion.  All this is happening at great speed – a red blood cell will circulate through the body and return to the heart every 60 seconds. 

Have you ever wondered why your skin will bleed when pricked with something as tiny as a pin?  There is a capillary exceedingly close to every cell in the body. Capillaries are the smallest and most numerous blood vessels in the body, with an inner diameter just wide enough for a red cell to squeeze through.  It is estimated that there are 25,000 miles of capillaries in an adult human body.

Blood vessels help to regulate body temperature by dilating close to the skin when we are overheated, as in a hot flash or after exercise.  Heat is thereby lost to the outside air.  When we are cold, blood vessels in the skin constrict, saving warmth in our core. (Shivering also helps to create more heat.)

We have 6-8 liters of blood in our adult bodies, or about 10 pints.  About 45% of this is cells, and 55% plasma.  Plasma is a watery tissue containing dissolved proteins (albumin, globulin and fibrinogen), glucose, blood fats, clotting factors, electrolytes, hormones and carbon dioxide.  It is the protein reserve for the body.
Red and white blood cells and platelets are produced in the bone marrow of our ribs, sternum, vertebrae and pelvis.   We produce billions of blood cells a day, to replace those that have a short life.  Red blood cells live 120 days, and white cells a much shorter time. Platelets are small clear cell fragments that are essential in preventing blood loss by forming a plug at the site of an injury.  Blood components come from stem cells - undifferentiated biological cells that can become specialized - in the bone marrow they give rise to red cells, white cells and platelets.
The blood clotting system consists of numerous factors that circulate continuously through the body in an inactive form. When platelets make a plug to stop bleeding, a substance called fibrin starts to form a clot, and the many  other clotting factors are activated in a chain reaction called the coagulation cascade.
This has been a simple explanation of the functions of blood, probably familiar to all readers.  In a subsequent column I will write a more detailed description of the immune system. In the meantime, here are some ideas for keeping your blood working well for you.
Avoid blood-born diseases such as Hepatitis B and C and AIDS by never sharing a needle, and practicing safe sex with condoms with any new partner.
Have a complete blood count (CBC) when you see your doctor, to test for anemia (this is especially important for women with heavy periods).  Eat iron containing foods and take an iron supplement if needed.  There are forms of anemia that do not require iron, but may require B vitamins.  Find out; don’t guess.  It’s important.
Breath deeply, exercise and keep good posture to fully oxygenate your blood.  Don’t smoke.  In addition to damaging your lungs, smoking constricts your blood vessels and impedes circulation to your heart, your limbs and your vital organs.
If you are taking a blood thinner such as Coumadin, aspirin, Pradaxa, or similar new anti-coagulants, keep something on hand that helps to stop bleeding from nosebleeds, small cuts or external injuries.  Several products are available on line and in pharmacies without a prescription, containing a powder that causes blood to coagulate.  You sprinkle it on the wound, or introduce it into your nose with an applicator, and then apply pressure.  I am familiar with a product called QR – it is quite helpful with small cuts or nosebleeds.  It should not be used if stitches are necessary, a wound is infected, or if bleeding is arterial.  For gushing arterial bleeding, apply direct pressure with a clean cloth or bandage, and get emergency help at once. 
Sadja Greenwood, MD    Past columns on this blog.  Check out my novel, Changing the Rules, at the Grand Hotel, Uniquities, the Stinson Beach and Point Reyes Book Stores, and Amazon.