as meal replacements or used in conjunction with reg-
ular food (e.g., sachet for breakfast, Tetra Brik for
lunch, and normal dinner).United States
Rights to the original Cambridge diet formula—a
powder to be mixed in a blender with water or diet soft
drinks—in the United States were obtained by Cam-
bridge Direct Sales in 1979. After working to improve
the formula’s flavor, the diet was placed on the market
in 1980. It was initially quite popular. The original
version of the Cambridge diet is sometimes known as
the ‘‘Original 330 Formula’’ in the company’s promo-
tional literature because Dr. Howard’s first rapid
weight-loss program called for a total daily consump-
tion of only 330 calories, provided by three servings of
the original powder formula (110 calories per serving).
The nutrient ratio of the original formula is 10–11 g of
proteinper serving, 15 g of carbohydrates (derived
primarily from fructose or fruit sugar), and 1 g of fat.
In 1984 Cambridge Direct Sales hired Dr. Robert
Nesheim to develop Cambridge Food for Life prod-
ucts. Like the Original 330 Formula, Food for Life is a
powder that comes in a can to be reconstituted with
conventional foods. Food for Life is available in a
super oats cereal version as well as flavor choices
including tomato, potato, mushroom, chicken soup,
vanilla, chocolate, strawberry, and eggnog. Nesheim
was specifically asked to meet guidelines for nutrition
supplements established by the U.S. Food and Drug
Administration (FDA). The company states that
Nesheim ‘‘increased the protein and carbohydrate
content for an extra margin of safety when used as
the sole source of nutrition.’’ Food for Life contains140 calories per serving, 13–15 g of protein, 18 g of
carbohydrates, and 1 g of fat.
The American company introduced a Cambridge
nutrition bar in 1983, but was unsuccessful as the
product had a short shelf life, and lacked flavor
appeal. Dr. Nesheim tripled the shelf life of the nutri-
tion bars and improved their taste. Each bar contains
170 calories, with 10 g of protein, 19–22 g of carbohy-
drates, and a low fat content.DescriptionBritish version
The British version of the Cambridge diet cannot
be used without the supervision of an official counselor,
who ‘‘provide[s] a personal screening, advisory, mon-
itoring and support service.’’ The counselors are trained
and accredited by the company, and must follow a code
of conduct in their dealings with customers. According
to the company, most counselors are people who have
successfully used the Cambridge diet themselves.
The British version of the Cambridge diet is for
adults over the age of 16 and has four stages:
Preparation: The dieter is asked to reduce food
intake gradually over a week to 10 days before begin-
ning the diet.
Losing weight: This initial step is called the ‘‘Sole
Source’’ program and gives the dieter between 415
and 554 calories per day. Dieters are advised not to
remain on the Sole Source program for longer than
four weeks at a time. They are required to obtain a
signed certificate from their doctor before they can
begin the Sole Source program. Female dieters shorter
than 5 ft 8 in take three servings of Cambridge dietKEY TERMS
Body mass index (BMI)—The ratio between a
person’s weight and the square of their height. A
BMI over 25 is considered overweight; below 20 is
considered underweight.
Cholelithiasis—The medical term for gallstones.
People on a VLCD have an increased risk of devel-
oping gallstones from an increase of cholesterol con-
tent in the bile produced by the liver.
Cognitive behavioral therapy (CBT)—An approach
to psychotherapy based on modifying the patient’s
day-to-day thoughts and behaviors, with the aim of
changing long-standing emotional patterns. Somepeople consider CBT a useful or even necessary
tool in maintaining long-term weight reduction.
Ketosis—An abnormal increase in the number of
ketone bodies in the body, produced when the liver
breaks down fat into fatty acids and ketone bodies.
Ketosis is a common side effect of low-carbohydrate
diets or VLCDs. If continued for a long period of
time, ketosis can cause serious damage to the kid-
neys and liver.
Very low-calorie diet (VLCD)—A term used by
nutritionists to classify weight-reduction diets that
allow around 800 calories or fewer a day.Cambridge diet