Pregnant and lactating women can use the Cambridge Diet as a nutritional supplement but not as their sole source of nutrition, because they may need more nutrients than other people.

The Cambridge Diet is specifically formulated with 44 grams of carbohydrates in addition to the protein and fat present. This combination produces a mild ketosis which can be a benefit to those on weight-loss programmes as it gives a slight euphoric effect while somewhat curbing the appetite.

Rapid weight-loss with very low calorie diets may temporarily affect the menstrual cycle patterns; ovulation, however, is not interrupted. This cycle is usually corrected within a few months, as body metabolism adjusts.

Check with your doctor before going on any diet. The Cambridge Diet is low in cholesterol, low in sodium and low in fat. It is recommended by most heart specialists.

There are no contra indications in using the Cambridge Diet. Scientists are looking closely at the relationship between cancer and proper nutrition, but you should check with your doctor before using the Diet.

We would recommend that anyone wishing to follow any weight loss programme at any calorific level should check with their doctor first. All Cambridge customers need to complete a Medical Record Form whether they plan to use the Diet with or without food. Anyone on prescribed medications or with a medical condition and planning to use the Diet at less than 1500 Kcal per day should seek their doctor's consent. The same contraindications for the 'Sole Source' programme apply to a diet of less than 1500 Kcal.

We recommend that all customers, even those in perfect health, should consult their doctor before starting any weight loss programme, particularly if a doctor has not been consulted during the previous 12 months. Obesity is a significant factor in a number of medical conditions and anyone who is obese may have developed a medical condition that they are unaware of. In the case of anyone who is on prescribed medication, or is suffering from a medical condition, the Consultant will ask for the doctor's signed confirmation that the information given on the Medical Record Form is correct.

Yes. Nobody with diabetes should attempt to lose weight without being supervised by his or her doctor. There are two types of diabetes: Type 1, which is insulin dependent Type 2, which is controlled either by diet, oral medication, in some case insulin or a combination of all 3.
Obesity may be associated with diabetes. An appropriate diet, with or without medication, can help by lowering blood glucose levels. Because of this, the customer must have the full agreement from their doctor or health care professional to say that they are willing to adjust medication and monitor the customer throughout the weight loss phase. Once at target weight, the doctor will reassess the patient's needs. Again, adopting the maintenance programme is a good long-term health strategy.

Ketosis is another name for the 'fat burning' process. Once the body has used up its stored carbohydrate, it then switches to using its other energy store - unwanted fat. A ketogenic diet is very low in carbohydrate. The body's stored fat is broken down into little fatty acid molecules called ketones and these circulate taking energy to all the tissues in the body. The Cambridge Diet has been carefully researched and formulated so that when used as 'Sole Source' it has just enough carbohydrate for immediate energy and none left over for storage; this induces a mild ketosis. The smallest intake of additional carbohydrate can upset this fragile balance and cause carbohydrate to be restored along with attendant water, causing a plateau or even weight gain! The mild ketosis is an intrinsic part of the design of the 'Sole Source' programme because it has significant benefits - it is the key to comfort for the dieter:

• It reduces the feeling of hunger - removing the temptation to err!
• It induces a sense of well-being with good energy levels

This is a simple urine test which indicates the presence of ketones. The mild ketosis induced by the Cambridge Diet ensures that sufficient ketones are produced to give adequate energy with some left over which are passed into the urine. Two simple tests are available from the chemist (and at a reduced price from Cambridge Health Plan) - Ketostix and Ketur-Test. They are plastic strips with a felt tip. The tip will react and turn pink if ketones are present in the urine. Most dieters achieve ketosis after three days on the 'Sole Source' programme. If, after this time, a test gives a negative reading (the tip does not change colour), it is reasonable to assume that the dieter is deviating from 'Sole Source' and taking in extra carbohydrate. On the other hand, a positive reading (the tip turns pink) can be very motivating for someone who is in a pre-menstrual plateau. It is tangible evidence that their body is indeed still burning off fat, even though the loss is not showing on the scales.

The metabolic rate represents the amount of energy the body is burning - it is the rate at which calories are used. Regardless of how you diet or how often, your metabolic rate is primarily determined by how much you weigh (see next question). In all methods of dieting there is an initial small reduction in metabolic rate by about 10-15%, this phase is known as 'diet mode'. It drops quickly when food is restricted and particularly on the 'Sole Source' programme, but it drops no further despite a prolonged period of further food deprivation. The metabolic rate returns to 'normal mode' when food intake returns to the appropriate amount for the actual energy expended to maintain the new weight. A lighter body will not need so many calories to move it round and will establish a metabolic rate appropriate to the new weight.

The Cambridge Diet has been carefully researched and formulated to have an exact amount of carbohydrate. Enough for immediate energy but nothing left over for storage. The bars each contain 10g more of carbohydrate than do the drinks. Three drinks add up to 42.9 carbohydrate, four drinks 57.2g, three drinks plus a bar 67.6g! For those who are carbohydrate sensitive the latter combination could be enough to bring them out of ketosis with a consequent loss of benefits.

Even when diet and fluid intake are the same, there are other variables to take into account. In Type 2 diabetes the pancreas is still producing some insulin, though not enough for the body's needs, and production levels may vary. The body's uptake of the insulin will also be variable. Exercise increases muscle uptake of glucose and therefore reduces blood glucose levels. So the timing of the blood glucose test in relation to pancreas activity, exercise, as well as medication, the last meal and stress levels is important - these can all influence blood sugar levels.
Note: oral hypoglycaemic medication should be discounted on the 'Sole Source' programme. VLCD lowers blood sugar levels and, combined with medication, could make them go too low. The risks from blood sugar falling too low are greater than those from temporary increased blood sugar - which will automatically drop on 'Sole Source', the adjustment takes place quickly.

'Sole Source' is not ideal for anyone who is below par. Also, cough and cold remedies contain carbohydrate which affects levels of ketosis and therefore the dieter's comfort. The Diet can be used as a nutritious part of a light diet with plenty of clear fluids for anyone who is unwell or who is convalescing. Use any over-the-counter remedy to relieve cough and cold symptoms and then, once you are fully recovered, you can restart 'Sole Source'.

The 'Sole Source' programme should not be followed for one week preceding blood donation and for one week after. In fact, a centre will refuse to take blood if they know the donor is on a very low calorie diet, because blood viscosity and volume are affected by the 'Sole Source' programme.