The first thing I hear when I talk about how much protein I eat is: “It’s bad for your kidneys!”
Are all these people doctors? Nephrologists? Therapists who are somehow related to the kidneys?
No, but somehow the average person simply knows that 35% of daily calories from protein harms the kidneys. If you eat a few chicken breasts, you will definitely end up on dialysis.
Ask these people how protein affects the kidneys, and you won't get a clear answer. This is not good.
Meanwhile, they, lovers of cola, French fries and physical inactivity, do not even think about the impact of their lifestyle on the body.
- Obesity, diabetes and kidney disease
- Diet
- High Protein + Strength Training = Fat Loss
Kidney functions
But does protein really harm your kidneys?
Before we revisit this concept, let's talk about what the kidneys do and the tests and indicators your doctor uses to make sure your kidneys are working properly.
The kidneys perform several functions:
The argument for protein damage to the kidney—if anyone can actually make it—is the theoretical increased burden of protein processing. That is, large amounts of protein lead to filtration problems, which then inevitably causes kidney damage or kidney failure.
Elevated protein in children
The causes of this pathology in children are the same as in adults. Outwardly this manifests itself as follows:
- sweating;
- weakness;
- partial or complete refusal of the child to eat;
- nausea, cases of vomiting are also common;
- chills;
- drowsiness;
- dizziness;
- pain in muscles and joints.
It is possible to reduce the amount of protein in a child’s urine only by eliminating the cause of its occurrence.
At the same time, according to pediatricians, the appearance of protein in a child should not plunge parents into panic. Because, for example, in newborns, proteinuria is considered normal and, in addition, they often react in a similar way to overfeeding. But due to the difficulties associated with the correct collection of urine from a baby, the protein content in it can be determined erroneously.
How to Assess Kidney Function
There are about a half-dozen measures used to measure kidney function, but they all measure how much fluid (blood plasma) the kidneys are filtering at any given time.
Glomerular filtration rate (GFR)
Creatinine clearance
Indirect methods for determining kidney function: urine albumin, urea and plasma creatinine
- Instead of trying to calculate the filtration rate, you can also look at the levels of substances in the plasma that the kidneys remove - creatinine and urea.
- High levels of creatinine or blood urea mean that the kidneys do not filter the plasma enough to get rid of excess of these substances.
- Normal creatinine levels range from 0.5 to 1.0 mg/dL (about 45-90 µmol/L) for women and 0.7 to 1.2 mg/dL (60-110 µmol/L) for men. The greater your muscle mass, the higher these numbers. Normal urea values are 10-20 mg/dL.
- A serum albumin test shows how much albumin protein is in the urine. Normally it shouldn't be there. If there is a little, this suggests that there is damage to the glomerulus that is allowing albumin to pass through it.
- Filtration of less than 20 mcg of albumin per minute is considered normal.
Thus, these indicators can be used to assess kidney function. This article uses the above samples as well as tests to determine the safety and benefit of a high-protein diet in people who are already at higher risk of kidney damage.
Treatment and prevention, what to do if protein appears in the urine
Having found out the primary sources of the process of the appearance of protein in urine, it is possible to take a number of preventive and therapeutic measures.
If proteins are found in the urine, then the analysis should initially be repeated, since laboratory assistants are also people and there may be errors in determining the indicators. Then an anamnesis is collected, concomitant diseases are found out that can cause changes in the level of protein in excreted urine.
The medicinal form of treatment consists of neutralizing its level to normal levels and eliminating symptoms. During the course of treatment, bed rest and dietary nutrition , aimed at limiting salt and liquid intake.
You should also give up alcohol, smoked meats, spicy foods, and protein foods.
The simultaneous use of aspirin, sulfonamides, and some antibiotics affects the indicators. So, additional treatment for other painful manifestations should be reported to the doctor when evaluating the results of a urine protein test.
The following groups of medications are used, if necessary:
- corticosteroid therapy;
- antirheumatic drugs and drugs that have an anti-inflammatory effect;
- ACE inhibitors;
- cytostatic drugs.
Traditional methods of treatment recommend the use of the following recipes...
- 4 large spoons of parsley seeds are poured into a glass of boiling water and infused for three hours. The resulting infusion is taken in small portions throughout the day.
- In the treatment of this pathology, cranberry received the highest recommendations. First squeeze the juice out of the berries, and make a decoction using the remaining pulp and skin, adding a small amount of water. After mixing both the resulting ingredients, consume the resulting mixture in small quantities throughout the day.
In pharmacies it is possible to purchase specialized herbal preparations, the regular use of which will help solve the problem of reducing protein in the urine.
Testing high protein diet and kidney function
So now that we know how to assess kidney function and potential damage, we can use these tests to find out whether high protein diets are actually harmful.
To understand this, we can test kidney function on a high protein diet in healthy people. Or we can go a step further and test high-protein diets in people whose kidney function is already compromised: obese diabetics.
Obesity, diabetes and kidney disease
Obesity and type 2 diabetes can cause and worsen already reduced kidney function. One large-scale study found, for example, that the incidence of end-stage renal disease depended on body mass index (BMI): as BMI increased, so did the rate of progression of kidney disease.
Mechanisms of cardiorenal injury are exacerbated by excess weight and poor diet.
Cocktails
Many people use protein shakes to lose weight. They give the desired effect, but when accompanied by a certain physical activity. They are prepared from kefir (milk) in combination with dried fruits.
The positive properties of such cocktails include:
- use instead of single-component food;
- no danger when used;
- obtaining the required action.
The negative aspects of using this food are:
- the appearance of problems with the digestive tract due to incorrect and irregular consumption of cocktails;
- disruption of the supply of required energy to the body;
- reducing the volume of consumption of other food products in order to prevent the occurrence of the opposite effect.
Methods
Participants were men and women with average scores:
Participants were divided into four groups:
The study lasted 16 weeks. Before and after the study, weight, body fat percentage, blood pressure, strength were measured, and blood was drawn.
Diet
The definition of "high protein" varies in the literature. For professional athletes and those who train on weight machines, the norm is 2.2-4.4 g of protein per kilogram of weight per day.
In this study, protein was considered high at 33% of daily calories, or about 1.2 g/kg/day. The HP group consumed about 2.04 g of protein per kg of body weight.
While this amount may be higher than what is found in typical nutritional guides, it is not a truly high-protein diet.
Workout
Groups 3 and 4 performed resistance training 3 times per week, with at least one rest day between training days.
Each workout consisted of eight exercises with 70-85% of maximum weight, 2 sets of 8-12 repetitions with 1-2 minutes of rest between sets. The weight was increased if subjects could do more than 12 repetitions in two sets.
Exercises:
All exercises, except the last one, were performed on simulators.
All in all, not a particularly impressive training program, but going from nothing to something improves strength and muscle mass anyway.
What is whey protein?
In sports nutrition, whey protein is mostly used, since it is as close as possible to natural protein, which the human body itself breaks down due to metabolic processes. Whey protein, like egg and meat protein, is a protein obtained through the use of a special technology for isolating it from ordinary products.
Products made in this way undergo the necessary purification, and a person involved in sports receives a completely finished dietary supplement that does not require additional effort from the body to process it. It only needs to break down proteins into amino acids and use them directly to form and maintain muscle mass.
Whey protein is natural to the human body. Its addition to the diet is considered advisable only when you need to quickly gain muscle mass and achieve this in the fastest and relatively safe way.
At the same time, it cannot be said that such a protein can be taken by everyone, without exception, who wants to bring their body into a sporty shape. If a person has an individual intolerance to protein, which manifests itself in the form of allergies or dysfunction of the digestive system, then its intake can be adjusted or supplemented with the necessary enzymes.
If there is no effect from the measures taken, you will have to stop taking whey protein. From the above it follows that this remedy does not pose potential harm on a large scale, the consequences of which may become irreversible. But if a person has any kidney diseases, the use of this dietary supplement is strictly prohibited.
results
High Protein + Strength Training = Fat Loss
All groups lost weight (see Figures 1 and 2).
However, the HP+RT group lost the most weight and fat (13.8 kg and 11.4 kg, respectively).
The HP + RT group also lost more fat around the waist: 11.4 cm compared to the other groups, which lost 8.2 cm (CON), 8.9 cm (HP) and 11.3 cm (CON + RT).
High protein + strength training = increased strength
The groups that trained (CON + RT & HP + RT) got stronger, while the other groups (CON & HP) got weaker, as can be seen in the 1 rep max (1 RM) bench press (Figure .3).
Blood counts
All groups had improvements in blood pressure at 16 weeks (15 mmHg reduction in systolic blood pressure and 8 mmHg reduction in diastolic blood pressure).
There were significant improvements in all groups:
There were no differences between the groups in blood counts, although the authors believe that having more people (increased statistical power) in the study would have helped to detect some difference. They claim that this would show improvement in blood counts in the HP+RT group as they had the greatest improvements across the board. But until such a study is conducted, this remains just speculation.
HDL cholesterol was an oddity: it decreased slightly (0.1 mmol/L) over 16 weeks in all groups except CON.
Designations
CON – hypocaloric diet (19% protein)
HP – hypocaloric high protein diet
CON + RT – CON diet with training
HP + RT – HP diet with training
Figure 1: Body weight lost after 16 weeks of the experiment.
Figure 2: Body fat lost after 16 weeks of the experiment.
High protein = no kidney problems
Since diabetes is the most common cause of kidney failure and obesity is a risk factor, it is easy to assume that these overweight and obese diabetics on a high protein diet will show signs of kidney dysfunction. But no.
Using creatinine clearance and urinary albumin to assess kidney function, the researchers found that there was no difference in these measures between the high-protein diet and control diet groups. Over time, there was a decrease in creatinine clearance but an improvement in microalbuminuria.
Symptoms of increased protein levels in urine
If the increase or appearance of proteins in the urine is temporary, then quite often this process occurs without any particularly pronounced symptoms.
The pathological process of proteinuria has the following characteristic symptoms.
- Painful sensations that occur in the joints and bones are signs of multiple myeloma.
- Increased fatigue.
- The presence of attacks of dizziness or drowsiness.
- Pronounced signs of swelling and hypertension, impending nephropathy with signs of chills and fever, tingling and a feeling of numbness in the fingers and toes.
- Sleep disturbance and short loss of consciousness.
- Anemia and, as a consequence, pallor of the epidermis, weakness and apathy.
- Painful muscle contractions.
- The color and consistency of urine changes, it becomes cloudy, flakes and a white coating are present.
- Increased body temperature and loss of appetite.
Summarizing
Training combined with a high protein diet (33% of calories) is more effective for fat loss than either a high protein diet alone or training with a lower protein diet (19%).
Overweight and obese diabetics on a high-protein diet and a control diet for 16 weeks had similar kidney function. The extra protein had no negative effects, even in people who are at higher risk of kidney damage.
Enjoy your squirrels!
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